INTRODUCTION
[0001] The following relates generally to wireless communications, and more specifically
to managing relay nodes with multiple backhaul connections.
[0002] Wireless communications systems are widely deployed to provide various types of communication
content such as voice, video, packet data, messaging, broadcast, and so on. These
systems may be capable of supporting communication with multiple users by sharing
the available system resources (e.g., time, frequency, and power). Examples of such
multiple-access systems include fourth generation (4G) systems such as Long Term Evolution
(LTE) systems, LTE-Advanced (LTE-A) systems, or LTE-A Pro systems, and fifth generation
(5G) systems which may be referred to as New Radio (NR) systems. These systems may
employ technologies such as code division multiple access (CDMA), time division multiple
access (TDMA), frequency division multiple access (FDMA), orthogonal frequency division
multiple access (OFDMA), or discrete Fourier transform-spread-OFDM (DFT-S-OFDM). A
wireless multiple-access communications system may include a number of base stations
or network access nodes, each simultaneously supporting communication for multiple
communication devices, which may be otherwise known as user equipment (UE).
[0003] In some wireless communications systems (e.g., 5G NR systems), infrastructure and
spectral resources for NR access may additionally support wireless backhaul link capabilities
in supplement to wireline backhaul connections, providing an integrated access and
backhaul (IAB) network architecture. One or more base stations may include centralized
units (CUs) and distributed units (DUs) and may be referred to as donor base stations.
One or more DUs associated with a donor base station may be partially controlled by
CUs associated with the donor base station. The one or more donor base stations (e.g.,
IAB donors) may be in communication with one or more additional base stations (e.g.,
IAB nodes or relay nodes) via supported access and backhaul links. IAB nodes may support
mobile terminal (MT) functionality controlled and/or scheduled by DUs of a coupled
IAB donor or parent IAB node, as well as DUs relative to additional entities (e.g.,
child IAB nodes, UEs, etc.) within the relay chain or configuration of the access
network.
[0004] In some cases, upstream connections in IAB networks (e.g., a connection between a
MT functionality of a relay node and a DU of a parent node) may deteriorate due to,
for example, loss of uplink synchronization, adverse channel conditions, communications
interference, etc. Such may result in reduced throughput, radio link failure (RLF)
procedures, increased latency, etc., which may hinder system performance.
[0005] 3GPP Draft R3-184934, "TP to TR 38.874 on Support for multiple path redundancy for
IAB nodes", Ericsson et al, focuses on solutions for supporting multiple paths whereby fast seamless mobility/redundancy
and even load balancing can be realized.
3GPP Draft R3-184935, "TP to TR 38.874 on using F1 functionality to support redundant
paths", Ericsson et al, focuses on reusing F1 functionality for supporting fast seamless mobility/redundancy
and load balancing.
3GPP Draft R3-185153, "Multi-connectivity Architecture Design for IAB Arch. 1a", AT&T, discusses issues related to multi-connectivity architecture design to support route
management in IAB architecture group 1a.
3GPP Draft R2-1806126, "Adaptation layer based L2 relaying and light L2 relaying",
Huawei et al, presents considerations about protocol stack design of IAB networks with two
candidates for Architecture 1a.
3GPP TR 38.374 V0.4.0, "3rd Generation Partnership Project; Technical Specification
Group Radio Access Network; Study on Integrated Access and Backhaul; (Release 15)", describes the architectures, the radio protocols, and the physical layer aspects
related to relaying of access traffic by sharing radio resources between access and
backhaul links.
3GPP Draft R3-183689, "Discussion on IAB node discovery and selection", ZTE, investigates IAB node cell selection/reselection criteria and access procedure.
SUMMARY
[0006] The invention is defined by the subject-matter of the independent claims. Preferred
embodiments are defined in the dependent claims.
BRIEF DESCRIPTION OF THE DRAWINGS
[0007]
FIG. 1 illustrates an example of a system for wireless communications that supports
relay nodes with multi-connected cellular backhaul in accordance with one or more
aspects of the present disclosure.
FIGs. 2 and 3 illustrate example wireless communications systems that support relay
nodes with multi-connected cellular backhaul in accordance with one or more aspects
of the present disclosure.
FIG. 4 illustrates an example of a flowchart that supports relay node with multi-connected
cellular backhaul in accordance with one or more aspects of the present disclosure.
FIG. 5 illustrates an example of a process flow that supports relay node with multi-connected
cellular backhaul in accordance with one or more aspects of the present disclosure.
FIG. 6 illustrates an example of a flowchart that supports relay node with multi-connected
cellular backhaul in accordance with one or more aspects of the present disclosure.
FIG. 7 illustrates an example of a process flow that supports relay node with multi-connected
cellular backhaul in accordance with one or more aspects of the present disclosure.
FIGs. 8 and 9 show block diagrams of devices that support relay nodes with multi-connected
cellular backhaul in accordance with one or more aspects of the present disclosure.
FIG. 10 shows a block diagram of a communications manager that supports relay nodes
with multi-connected cellular backhaul in accordance with one or more aspects of the
present disclosure.
FIG. 11 shows a diagram of a system including a device that supports relay nodes with
multi-connected cellular backhaul in accordance with one or more aspects of the present
disclosure.
FIGs. 12 and 13 show block diagrams of devices that support relay nodes with multi-connected
cellular backhaul in accordance with one or more aspects of the present disclosure.
FIG. 14 shows a block diagram of a communications manager that supports relay nodes
with multi-connected cellular backhaul in accordance with one or more aspects of the
present disclosure.
FIG. 15 shows a diagram of a system including a device that supports relay nodes with
multi-connected cellular backhaul in accordance with one or more aspects of the present
disclosure.
FIGs. 16 through 20 show flowcharts illustrating methods that support relay nodes
with multi-connected cellular backhaul in accordance with one or more aspects of the
present disclosure.
DETAILED DESCRIPTION
[0008] In the following embodiments falling under the scope of the claims are indicated.
Other aspects or embodiments that do not fall under the scope of the claims are useful
to understand the invention.
[0009] In some wireless communications systems (e.g., 5G NR systems), infrastructure and
spectral resources for NR access may additionally support wireless backhaul link capabilities
in supplement to wireline backhaul connections, providing an IAB network architecture.
One or more base stations may include CUs and DUs and may be referred to as donor
base stations (e.g., or IAB donors). One or more DUs associated with a donor base
station may be partially controlled by CUs associated with the donor base station.
A base station CU may be a component of a database, data center, core network, or
network cloud. A network node associated with a RAT may communicate with a donor base
station CU via a backhaul link (e.g., wireline backhaul or wireless backhaul). The
one or more donor base stations (e.g., IAB donors) may be in communication with one
or more additional base stations (e.g., IAB nodes or relay nodes) and UEs. IAB nodes
may support MT functionality controlled and scheduled by an IAB donor and/or parent
IAB nodes relative to the MT supported IAB nodes. IAB nodes may additionally support
DU operability relative to additional entities (e.g., child IAB nodes, UEs, etc.)
within the relay chain or configuration of the access network (e.g., relative to entities
downstream from the IAB node). For example, an IAB network architecture may include
a chain of connected wireless devices (e.g., starting with a donor base station and
ending with a UE, with any number of IAB relay nodes in between) via link resources
that support NR access and backhaul capabilities (e.g., a wireline backhaul or wireless
backhaul).
[0010] A relay node may refer to an intermediary node in a relay chain (e.g., an IAB relay
chain). For example, a relay node may relay communications between a parent node (e.g.,
an IAB donor, or an IAB node upstream or higher on the relay chain) and a child node
(e.g., an IAB node downstream or lower on the relay chain). In some cases, the relay
node may refer to the DU or access node function (AN-F) of an intermediary IAB node.
A child node may refer to an IAB-Node (e.g., the MT of the IAB-Node) or a UE that
is the child of another IAB-Node (e.g., such as the relay node). A parent node in
communication with the relay node may refer to an upstream IAB-Node or an IAB-donor
(e.g., the DU/AN-F of the IAB-Node or IAB-Donor). In some cases, a parent node may
be referred to as a control node (e.g., a control node may refer to a parent node
or a DU of a parent node in communication with an MT of a relay node or other intermediary
IAB node).
[0011] Techniques provided herein may enhance the efficiency of certain wireless communications
systems, including systems that use wireless connections between nodes (e.g., base
stations) for backhaul communications. In wireless communications systems that employ
wireline links for backhaul communications, a wireless node may enjoy a robust wireline
link to a network entity that coordinates aspects of backhaul communications (e.g.,
the network entity provides timing information, cell identity, etc.) for neighboring
nodes to coordinate backhaul transmissions. However, in some systems, deploying a
wireline link to wireless nodes may result in substantial expense and resource expenditure.
For example, wireless nodes operating in millimeter wave (mmW) frequency ranges may
be associated with a reduced coverage area (e.g., a smaller geographic footprint,
directional transmissions, etc.), which may result in a deployment of a larger number
of access nodes (e.g., wireless nodes or IAB nodes) to provide acceptable coverage
areas to users. As a result, a number of wireless nodes within the wireless communication
system may not be coupled with a wireline backhaul link and may instead use wireless
backhaul links for backhaul communications in a wireless backhaul network (e.g., such
as an IAB network).
[0012] The described techniques provide for maintenance of wireless backhaul connections
through use of multiple wireless backhaul links. For example, in some cases, a relay
node may support multiple MT functionalities (e.g., a relay node may include multiple
MT entities), and may connect to different parent IAB nodes using the different MT
functionalities. As such, a relay node may establish multiple paths (e.g., redundant
paths) for multiple wireless backhaul links. That is, a relay node may establish multiple
wireless backhaul links through different paths of the relay chain via multiple MT
links to different parent nodes connected to the same CU or network management function.
In some cases, all of the established wireless backhaul links (e.g., wireless backhaul
links established by each MT of the relay node) may be used in parallel (e.g., simultaneously)
for backhaul communications. In other cases, a subset of the wireless backhaul links
may be used for backhaul communications, and the remaining wireless backhaul links
may be used for backup purposes (e.g., in cases where the subset of backhaul links
deteriorates due to loss of uplink synchronization, poor channel conditions, communications
interference, etc.).
[0013] The described techniques further provide mechanisms for network management function
(e.g., network or CU) coordination and configuration of such multiple wireless backhaul
links. In some cases, where a relay node supports multiple (e.g., more than 1) MT
functionalities, the network management function may be informed of the relay nodes
capabilities relating to MT functionality. For example, a relay node may establish
a first backhaul link to the network management function using a first MT function
(e.g., to a first parent node). The relay node may use the first backhaul link to
transmit a capability report (e.g., a list or identifiers of additional supported
MT functions, RATs supported by the additional MT functions, frequency bands supported
by the additional MT functions, RF capabilities of the additional MT functions, etc.)
to the network management function (e.g., via the first backhaul link to the first
parent node). The network management function may then identify a measurement configuration
for some or all of the additional MT functions of the relay node based on the capability
report (e.g., based on the capabilities of the additional MT functions supported by
the relay node). The network management function may transmit the measurement configuration
to the relay node via the first backhaul link. The relay node may perform, using one
or all of the additional MT functions, measurements of parent nodes in accordance
with the measurement configuration (e.g., the measurement configuration may include
identification of the additional MT functions to perform the measuring, identification
of parent nodes to be measured, etc.). The relay node may then transmit, using the
first MT function of the relay node, the measurement report to the network management
function via the first backhaul link.
[0014] The network management function may thus coordinate and configure additional backhaul
links for the relay node based on the received measurement report. For example, the
network management function may transmit a backhaul link configuration for the second
MT function to the relay node via the first backhaul link, and the relay node may
establish a second wireless backhaul link to a second parent node (e.g., where the
second MT function and the second parent node may be indicated by the backhaul link
configuration).
[0015] In other examples, multiple MT functions of a relay node may autonomously connect
to different parent nodes (e.g., which may or may not be associated with a same network
management function). For example, in some cases, MT functions of a relay node may
autonomously search for a parent node (e.g., perform parent node transmission measurements).
In such examples, the relay node may exchange (e.g., using a first MT function of
the relay node) an identifier of the relay node with a first network management function
via a first backhaul link to a first parent node. The relay node may also transmit
(e.g., using a second MT function of the relay node) the identifier of the relay node
to a second network management function via a second backhaul link to a second parent
node. As such, in cases where both parent nodes (e.g., or backhaul links) are associated
with the same network management function, the management function may receive the
relay node identifiers via the two backhaul links and may identify the relay node
is capable of supporting the multiple backhaul links. In such cases, the network management
function may transmit a backhaul link configuration (e.g., for the first MT function,
the second MT function, or both) to the relay node (e.g., via the first backhaul link,
the second backhaul link, or both) based on the identification that the relay node
supports multiple backhaul link connections.
[0016] Beneficially, techniques supporting relay nodes with multi-connected backhaul links
(e.g., multi-hop backhaul links) as described herein may improve backhaul communication
robustness (e.g., may reduce service interruption, signaling delay, etc. associated
with a deteriorating wireless backhaul link, through use of additional wireless backhaul
links). A network management function may identify that a relay node supports multiple
backhaul connections, and may coordinate and configure the multiple backhaul connections
using the techniques described herein. For example, the network management function
may thus configure use of parallel wireless backhaul links (e.g., which may increase
backhaul throughput, add wireless link redundancy for more reliable backhaul communications,
etc.). In other examples, the network management function may configure backup wireless
backhaul links (e.g., which may be used in cases where the first or primary wireless
backhaul link deteriorates, when the measurement report indicates a second wireless
backhaul link may be more reliable, etc.).
[0017] Aspects of the disclosure are initially described in the context of a wireless communications
system. Example wireless communications systems, flowcharts, and process flows implementing
the discussed techniques are then described. Aspects of the disclosure are further
illustrated by and described with reference to apparatus diagrams, system diagrams,
and flowcharts that relate to relay nodes with multi-connected cellular backhaul.
[0018] FIG. 1 illustrates an example of a wireless communications system 100 that supports relay
nodes with multi-connected cellular backhaul in accordance with one or more aspects
of the present disclosure. The wireless communications system 100 includes network
devices 105, UEs 115, and a core network 130. In some examples, the wireless communications
system 100 may be a LTE network, a LTE-A network, a LTE-A Pro network, or a NR network.
In some cases, wireless communications system 100 may support enhanced broadband communications,
ultra-reliable (e.g., mission critical) communications, low latency communications,
or communications with low-cost and low-complexity devices. Wireless communications
system 100 may support signaling between network devices 105 for establishment of
multiple backhaul connections for relay nodes (e.g., network devices 105) supporting
multiple MT functions.
[0019] The core network 130 may provide user authentication, access authorization, tracking,
Internet Protocol (IP) connectivity, and other access, routing, or mobility functions.
The core network 130 may be an evolved packet core (EPC), which may include at least
one mobility management entity (MME), at least one serving gateway (S-GW), and at
least one Packet Data Network (PDN) gateway (P-GW). The MME may manage non-access
stratum (e.g., control plane) functions such as mobility, authentication, and bearer
management for UEs 115 served by network devices 105 associated with the EPC. User
IP packets may be transferred through the S-GW, which itself may be connected to the
P-GW. The P-GW may provide IP address allocation as well as other functions. The P-GW
may be connected to the network operators IP services. The operators IP services may
include access to the Internet, Intranet(s), an IP Multimedia Subsystem (IMS), or
a Packet-Switched (PS) Streaming Service.
[0020] At least some of the network devices 105 (e.g., network device 105-a), which may
be an example of a base station (e.g., eNB, network access devices, gNB), or network
device 105-b, which may be an example of an access node controller (ANC)), may interface
with the core network 130 through backhaul links 132 (e.g., S1, S2) and may perform
radio configuration and scheduling for communication with the UEs 115. In various
examples, the network devices 105-b may communicate, either directly or indirectly
(e.g., through core network 130), with each other over backhaul links 134 (e.g., X1,
X2), which may be wired or wireless communication links.
[0021] Each network device 105-b may also additionally or alternatively communicate with
a number of UEs 115 through a number of other network devices 105-c, where network
device 105-c may be an example of a smart radio head (or through a number of smart
radio heads). In alternative configurations, various functions of each network device
105 may be distributed across various network devices 105 (e.g., radio heads and access
network controllers) or consolidated into a single network device 105 (e.g., a base
station).
[0022] Network devices 105 may wirelessly communicate with UEs 115 via one or more base
station antennas. Network device 105 described herein may include or may be referred
to by those skilled in the art as a base transceiver station, a radio base station,
an access point, a radio transceiver, a NodeB, an eNB, a next-generation Node B or
giga-nodeB (either of which may be referred to as a gNB), a Home NodeB, a Home eNodeB,
or some other suitable terminology. Wireless communications system 100 may include
network devices 105 of different types (e.g., macro or small cell base stations).
The UEs 115 described herein may be able to communicate with various types of network
devices 105 and network equipment including macro eNBs, small cell eNBs, gNBs, relay
base stations, and the like.
[0023] Each network device 105 may be associated with a particular geographic coverage area
110 in which communications with various UEs 115 is supported. Each network device
105 may provide communication coverage for a respective geographic coverage area 110
via communication links 125, and communication links 125 between a network device
105 and a UE 115 may utilize one or more carriers. Communication links 125 shown in
wireless communications system 100 may include uplink transmissions from a UE 115
to a network device 105, or downlink transmissions from a network device 105 to a
UE 115. Downlink transmissions may also be called forward link transmissions while
uplink transmissions may also be called reverse link transmissions.
[0024] The geographic coverage area 110 for a network device 105 may be divided into sectors
making up only a portion of the geographic coverage area 110, and each sector may
be associated with a cell. For example, each network device 105 may provide communication
coverage for a macro cell, a small cell, a hot spot, or other types of cells, or various
combinations thereof. In some examples, a network device 105 may be movable and therefore
provide communication coverage for a moving geographic coverage area 110. In some
examples, different geographic coverage areas 110 associated with different technologies
may overlap, and overlapping geographic coverage areas 110 associated with different
technologies may be supported by the same network device 105 or by different network
devices 105. The wireless communications system 100 may include, for example, a heterogeneous
LTE/LTE-A/LTE-A Pro or NR network in which different types of network devices 105
provide coverage for various geographic coverage areas 110.
[0025] The term "cell" refers to a logical communication entity used for communication with
a network device 105 (e.g., over a carrier), and may be associated with an identifier
for distinguishing neighboring cells (e.g., a physical cell identifier (PCID), a virtual
cell identifier (VCID)) operating via the same or a different carrier. In some examples,
a carrier may support multiple cells, and different cells may be configured according
to different protocol types (e.g., machine-type communication (MTC), narrowband Internet-of-Things
(NB-IoT), enhanced mobile broadband (eMBB), or others) that may provide access for
different types of devices. In some cases, the term "cell" may refer to a portion
of a geographic coverage area 110 (e.g., a sector) over which the logical entity operates.
[0026] UEs 115 may be dispersed throughout the wireless communications system 100, and each
UE 115 may be stationary or mobile. A UE 115 may also be referred to as a mobile device,
a wireless device, a remote device, a handheld device, or a subscriber device, or
some other suitable terminology, where the "device" may also be referred to as a unit,
a station, a terminal, or a client. A UE 115 may also be a personal electronic device
such as a cellular phone, a personal digital assistant (PDA), a tablet computer, a
laptop computer, or a personal computer. In some examples, a UE 115 may also refer
to a wireless local loop (WLL) station, an Internet of Things (IoT) device, an Internet
of Everything (IoE) device, or an MTC device, or the like, which may be implemented
in various articles such as appliances, vehicles, meters, or the like. A UE 115 may
communicate with the core network 130 through communication link 135.
[0027] Some UEs 115, such as MTC or IoT devices, may be low cost or low complexity devices,
and may provide for automated communication between machines (e.g., via Machine-to-Machine
(M2M) communication). M2M communication or MTC may refer to data communication technologies
that allow devices to communicate with one another or a network device 105 without
human intervention. In some examples, M2M communication or MTC may include communications
from devices that integrate sensors or meters to measure or capture information and
relay that information to a central server or application program that can make use
of the information or present the information to humans interacting with the program
or application. Some UEs 115 may be designed to collect information or enable automated
behavior of machines. Examples of applications for MTC devices include smart metering,
inventory monitoring, water level monitoring, equipment monitoring, healthcare monitoring,
wildlife monitoring, weather and geological event monitoring, fleet management and
tracking, remote security sensing, physical access control, and transaction-based
business charging.
[0028] Some UEs 115 may be configured to employ operating modes that reduce power consumption,
such as half-duplex communications (e.g., a mode that supports one-way communication
via transmission or reception, but not transmission and reception simultaneously).
In some examples half-duplex communications may be performed at a reduced peak rate.
Other power conservation techniques for UEs 115 include entering a power saving "deep
sleep" mode when not engaging in active communications, or operating over a limited
bandwidth (e.g., according to narrowband communications). In some cases, UEs 115 may
be designed to support critical functions (e.g., mission critical functions), and
a wireless communications system 100 may be configured to provide ultra-reliable communications
for these functions.
[0029] In some cases, a UE 115 may also be able to communicate directly with other UEs 115
(e.g., using a peer-to-peer (P2P) or device-to-device (D2D) protocol). One or more
of a group of UEs 115 utilizing D2D communications may be within the geographic coverage
area 110 of a network device 105. Other UEs 115 in such a group may be outside the
geographic coverage area 110 of a network device 105, or be otherwise unable to receive
transmissions from a network device 105. In some cases, groups of UEs 115 communicating
via D2D communications may utilize a one-to-many (1:M) system in which each UE 115
transmits to every other UE 115 in the group. In some cases, a network device 105
facilitates the scheduling of resources for D2D communications. In other cases, D2D
communications are carried out between UEs 115 without the involvement of a network
device 105.
[0030] Network devices 105 may communicate with the core network 130 and with one another.
For example, network devices 105 may interface with the core network 130 through backhaul
links 132 (e.g., via an S1, N2, N3, or other interface). Network devices 105 may communicate
with one another over backhaul links 134 (e.g., via an X2, Xn, or other interface)
either directly (e.g., directly between network devices 105) or indirectly (e.g.,
via core network 130).
[0031] Network devices 105 may support functionality for operations in an IAB network. For
example, network devices 105 may be split into support entities (e.g., functionalities)
for promoting wireless backhaul density in collaboration with NR communication access.
In some cases, one or more network devices 105 may be split into associated base station
CU and DU entities, where one or more DUs may be partially controlled by an associated
CU. The CU entities of the one or more network devices 105 may facilitate connection
between the core network 130 and the access network (e.g., via a wireline or wireless
connection to the core network). The DUs of the one or more network devices 105 may
control and/or schedule functionality for additional devices (e.g., one or more alternative
network devices 105, UEs 115) according to configured access and backhaul links. Based
on the supported entities at the one or more network devices 105, the one or more
network devices 105 may be referred to as donor network devices (e.g., or IAB donors,
donor base stations, etc.).
[0032] Additionally, in some cases, one or more network devices 105 may be split into associated
MT and base station DU entities, where MT functionality of the one or more network
devices 105 may be controlled and/or scheduled by the DU entities of the one or more
donor network devices (e.g., via a Uu interface). DUs associated with the one or more
network devices may be controlled by MT functionality. In addition, DUs of the one
or more network devices 105 may be partially controlled by signaling messages from
CU entities of associated donor network devices on the configured access and backhaul
links of a network connection (e.g., via an F1-AP). The DUs of the one or more network
devices 105 may support one of multiple serving cell coverage areas 110 of the network
coverage area. The DUs of the one or more network devices 105 may control and/or schedule
functionality for additional devices (e.g., one or more other network devices 105,
UEs 115) according to configured access and backhaul links. Based on the supported
entities at the one or more network devices 105, the base stations may be referred
to as intermediary network devices (e.g., or IAB nodes, intermediary base stations,
etc.).
[0033] At least some of the network devices, such as a network device 105, may include subcomponents
such as an access network entity, which may be an example of an ANC. Each access network
entity may communicate with UEs 115 through a number of other access network transmission
entities, which may be referred to as a radio head, a smart radio head, or a transmission/reception
point (TRP). In some configurations, various functions of each access network entity
or network device 105 may be distributed across various network devices (e.g., radio
heads and access network controllers) or consolidated into a single network device
(e.g., a network device 105).
[0034] Wireless communications system 100 may operate using one or more frequency bands,
typically in the range of 300 MHz to 300 GHz. Generally, the region from 300 MHz to
3 GHz is known as the ultra-high frequency (UHF) region or decimeter band, since the
wavelengths range from approximately one decimeter to one meter in length. UHF waves
may be blocked or redirected by buildings and environmental features. However, the
waves may penetrate structures sufficiently for a macro cell to provide service to
UEs 115 located indoors. Transmission of UHF waves may be associated with smaller
antennas and shorter range (e.g., less than 100 km) compared to transmission using
the smaller frequencies and longer waves of the high frequency (HF) or very high frequency
(VHF) portion of the spectrum below 300 MHz.
[0035] Wireless communications system 100 may also operate in a super high frequency (SHF)
region using frequency bands from 3 GHz to 30 GHz, also known as the centimeter band.
The SHF region includes bands such as the 5 GHz industrial, scientific, and medical
(ISM) bands, which may be used opportunistically by devices that can tolerate interference
from other users.
[0036] Wireless communications system 100 may also operate in an extremely high frequency
(EHF) region of the spectrum (e.g., from 30 GHz to 300 GHz), also known as the millimeter
band. In some examples, wireless communications system 100 may support mmW communications
between UEs 115 and network devices 105, and EHF antennas of the respective devices
may be even smaller and more closely spaced than UHF antennas. In some cases, this
may facilitate use of antenna arrays within a UE 115. However, the propagation of
EHF transmissions may be subject to even greater atmospheric attenuation and shorter
range than SHF or UHF transmissions. Techniques disclosed herein may be employed across
transmissions that use one or more different frequency regions, and designated use
of bands across these frequency regions may differ by country or regulating body.
[0037] In some cases, wireless communications system 100 may utilize both licensed and unlicensed
radio frequency spectrum bands. For example, wireless communications system 100 may
employ License Assisted Access (LAA), LTE-Unlicensed (LTE-U) radio access technology,
or NR technology in an unlicensed band such as the 5 GHz ISM band. When operating
in unlicensed radio frequency spectrum bands, wireless devices such as network devices
105 and UEs 115 may employ listen-before-talk (LBT) procedures to ensure a frequency
channel is clear before transmitting data. In some cases, operations in unlicensed
bands may be based on a CA configuration in conjunction with CCs operating in a licensed
band (e.g., LAA). Operations in unlicensed spectrum may include downlink transmissions,
uplink transmissions, peer-to-peer transmissions, or a combination of these. Duplexing
in unlicensed spectrum may be based on frequency division duplexing (FDD), time division
duplexing (TDD), or a combination of both.
[0038] In some examples, network device 105 or UE 115 may be equipped with multiple antennas,
which may be used to employ techniques such as transmit diversity, receive diversity,
multiple-input multiple-output (MIMO) communications, or beamforming. For example,
wireless communications system 100 may use a transmission scheme between a transmitting
device (e.g., a network device 105) and a receiving device (e.g., a UE 115), where
the transmitting device is equipped with multiple antennas and the receiving devices
are equipped with one or more antennas. MIMO communications may employ multipath signal
propagation to increase the spectral efficiency by transmitting or receiving multiple
signals via different spatial layers, which may be referred to as spatial multiplexing.
The multiple signals may, for example, be transmitted by the transmitting device via
different antennas or different combinations of antennas. Likewise, the multiple signals
may be received by the receiving device via different antennas or different combinations
of antennas. Each of the multiple signals may be referred to as a separate spatial
stream, and may carry bits associated with the same data stream (e.g., the same codeword)
or different data streams. Different spatial layers may be associated with different
antenna ports used for channel measurement and reporting. MIMO techniques include
single-user MIMO (SU-MIMO) where multiple spatial layers are transmitted to the same
receiving device, and multiple-user MIMO (MU-MIMO) where multiple spatial layers are
transmitted to multiple devices.
[0039] Beamforming, which may also be referred to as spatial filtering, directional transmission,
or directional reception, is a signal processing technique that may be used at a transmitting
device or a receiving device (e.g., a network device 105 or a UE 115) to shape or
steer an antenna beam (e.g., a transmit beam or receive beam) along a spatial path
between the transmitting device and the receiving device. Beamforming may be achieved
by combining the signals communicated via antenna elements of an antenna array such
that signals propagating at particular orientations with respect to an antenna array
experience constructive interference while others experience destructive interference.
The adjustment of signals communicated via the antenna elements may include a transmitting
device or a receiving device applying certain amplitude and phase offsets to signals
carried via each of the antenna elements associated with the device. The adjustments
associated with each of the antenna elements may be defined by a beamforming weight
set associated with a particular orientation (e.g., with respect to the antenna array
of the transmitting device or receiving device, or with respect to some other orientation).
[0040] In one example, a network device 105 may use multiple antennas or antenna arrays
to conduct beamforming operations for directional communications with a UE 115. For
instance, some signals (e.g. synchronization signals, reference signals, beam selection
signals, or other control signals) may be transmitted by a network device 105 multiple
times in different directions, which may include a signal being transmitted according
to different beamforming weight sets associated with different directions of transmission.
Transmissions in different beam directions may be used to identify (e.g., by the network
device 105 or a receiving device, such as a UE 115) a beam direction for subsequent
transmission and/or reception by the network device 105. Some signals, such as data
signals associated with a particular receiving device, may be transmitted by a network
device 105 in a single beam direction (e.g., a direction associated with the receiving
device, such as a UE 115). In some examples, the beam direction associated with transmissions
along a single beam direction may be determined based at least in in part on a signal
that was transmitted in different beam directions. For example, a UE 115 may receive
one or more of the signals transmitted by the network device 105 in different directions,
and the UE 115 may report to the network device 105 an indication of the signal it
received with a highest signal quality, or an otherwise acceptable signal quality.
Although these techniques are described with reference to signals transmitted in one
or more directions by a network device 105, a UE 115 may employ similar techniques
for transmitting signals multiple times in different directions (e.g., for identifying
a beam direction for subsequent transmission or reception by the UE 115), or transmitting
a signal in a single direction (e.g., for transmitting data to a receiving device).
[0041] A receiving device (e.g., a UE 115, which may be an example of a mmW receiving device)
may try multiple receive beams when receiving various signals from the network device
105, such as synchronization signals, reference signals, beam selection signals, or
other control signals. For example, a receiving device may try multiple receive directions
by receiving via different antenna subarrays, by processing received signals according
to different antenna subarrays, by receiving according to different receive beamforming
weight sets applied to signals received at a plurality of antenna elements of an antenna
array, or by processing received signals according to different receive beamforming
weight sets applied to signals received at a plurality of antenna elements of an antenna
array, any of which may be referred to as "listening" according to different receive
beams or receive directions. In some examples a receiving device may use a single
receive beam to receive along a single beam direction (e.g., when receiving a data
signal). The single receive beam may be aligned in a beam direction determined based
at least in part on listening according to different receive beam directions (e.g.,
a beam direction determined to have a highest signal strength, highest signal-to-noise
ratio, or otherwise acceptable signal quality based at least in part on listening
according to multiple beam directions).
[0042] In some cases, the antennas of a network device 105 or UE 115 may be located within
one or more antenna arrays, which may support MIMO operations, or transmit or receive
beamforming. For example, one or more base station antennas or antenna arrays may
be co-located at an antenna assembly, such as an antenna tower. In some cases, antennas
or antenna arrays associated with a network device 105 may be located in diverse geographic
locations. A network device 105 may have an antenna array with a number of rows and
columns of antenna ports that the network device 105 may use to support beamforming
of communications with a UE 115. Likewise, a UE 115 may have one or more antenna arrays
that may support various MIMO or beamforming operations.
[0043] In some cases, wireless communications system 100 may be a packet-based network that
operate according to a layered protocol stack. In the user plane, communications at
the bearer or Packet Data Convergence Protocol (PDCP) layer may be IP-based. A Radio
Link Control (RLC) layer may in some cases perform packet segmentation and reassembly
to communicate over logical channels. A Medium Access Control (MAC) layer may perform
priority handling and multiplexing of logical channels into transport channels. The
MAC layer may also use hybrid automatic repeat request (HARQ) to provide retransmission
at the MAC layer to improve link efficiency. In the control plane, the RRC protocol
layer may provide establishment, configuration, and maintenance of an RRC connection
between a UE 115 and a network device 105 or core network 130 supporting radio bearers
for user plane data. At the Physical (PHY) layer, transport channels may be mapped
to physical channels.
[0044] In some cases, UEs 115 and network devices 105 may support retransmissions of data
to increase the likelihood that data is received successfully. HARQ feedback is one
technique of increasing the likelihood that data is received correctly over a communication
link 125. HARQ may include a combination of error detection (e.g., using a cyclic
redundancy check (CRC)), forward error correction (FEC), and retransmission (e.g.,
automatic repeat request (ARQ)). HARQ may improve throughput at the MAC layer in poor
radio conditions (e.g., signal-to-noise conditions). In some cases, a wireless device
may support same-slot HARQ feedback, where the device may provide HARQ feedback in
a specific slot for data received in a previous symbol in the slot. In other cases,
the device may provide HARQ feedback in a subsequent slot, or according to some other
time interval.
[0045] Time intervals in LTE or NR may be expressed in multiples of a basic time unit, which
may, for example, refer to a sampling period of T
s = 1/30,720,000 seconds. Time intervals of a communications resource may be organized
according to radio frames each having a duration of 10 milliseconds (ms), where the
frame period may be expressed as T
f = 307,200 T
s. The radio frames may be identified by a system frame number (SFN) ranging from 0
to 1023. Each frame may include 10 subframes numbered from 0 to 9, and each subframe
may have a duration of 1 ms. A subframe may be further divided into 2 slots each having
a duration of 0.5 ms, and each slot may contain 6 or 7 modulation symbol periods (e.g.,
depending on the length of the cyclic prefix prepended to each symbol period). Excluding
the cyclic prefix, each symbol period may contain 2048 sampling periods. In some cases,
a subframe may be the smallest scheduling unit of the wireless communications system
100, and may be referred to as a transmission time interval (TTI). In other cases,
a smallest scheduling unit of the wireless communications system 100 may be shorter
than a subframe or may be dynamically selected (e.g., in bursts of shortened TTIs
(sTTIs) or in selected component carriers using sTTIs).
[0046] In some wireless communications systems, a slot may further be divided into multiple
mini-slots containing one or more symbols. In some instances, a symbol of a mini-slot
or a mini-slot may be the smallest unit of scheduling. Each symbol may vary in duration
depending on the subcarrier spacing or frequency band of operation, for example. Further,
some wireless communications systems may implement slot aggregation in which multiple
slots or mini-slots are aggregated together and used for communication between a UE
115 and a network device 105.
[0047] The term "carrier" refers to a set of radio frequency spectrum resources having a
defined physical layer structure for supporting communications over a communication
link 125. For example, a carrier of a communication link 125 may include a portion
of a radio frequency spectrum band that is operated according to physical layer channels
for a given radio access technology. Each physical layer channel may carry user data,
control information, or other signaling. A carrier may be associated with a pre-defined
frequency channel (e.g., an E-UTRA absolute radio frequency channel number (EARFCN)),
and may be positioned according to a channel raster for discovery by UEs 115. Carriers
may be downlink or uplink (e.g., in an FDD mode), or be configured to carry downlink
and uplink communications (e.g., in a TDD mode). In some examples, signal waveforms
transmitted over a carrier may be made up of multiple sub-carriers (e.g., using multi-carrier
modulation (MCM) techniques such as OFDM or DFT-s-OFDM).
[0048] The organizational structure of the carriers may be different for different radio
access technologies (e.g., LTE, LTE-A, LTE-A Pro, NR, etc.). For example, communications
over a carrier may be organized according to TTIs or slots, each of which may include
user data as well as control information or signaling to support decoding the user
data. A carrier may also include dedicated acquisition signaling (e.g., synchronization
signals or system information, etc.) and control signaling that coordinates operation
for the carrier. In some examples (e.g., in a carrier aggregation configuration),
a carrier may also have acquisition signaling or control signaling that coordinates
operations for other carriers.
[0049] Physical channels may be multiplexed on a carrier according to various techniques.
A physical control channel and a physical data channel may be multiplexed on a downlink
carrier, for example, using time division multiplexing (TDM) techniques, frequency
division multiplexing (FDM) techniques, or hybrid TDM-FDM techniques. In some examples,
control information transmitted in a physical control channel may be distributed between
different control regions in a cascaded manner (e.g., between a common control region
or common search space and one or more UE-specific control regions or UE-specific
search spaces).
[0050] A carrier may be associated with a particular bandwidth of the radio frequency spectrum,
and in some examples the carrier bandwidth may be referred to as a "system bandwidth"
of the carrier or the wireless communications system 100. For example, the carrier
bandwidth may be one of a number of predetermined bandwidths for carriers of a particular
radio access technology (e.g., 1.4, 3, 5, 10, 15, 20, 40, or 80 MHz). In some examples,
each served UE 115 may be configured for operating over portions or all of the carrier
bandwidth. In other examples, some UEs 115 may be configured for operation using a
narrowband protocol type that is associated with a predefined portion or range (e.g.,
set of subcarriers or RBs) within a carrier (e.g., "in-band" deployment of a narrowband
protocol type).
[0051] In a system employing MCM techniques, a resource element may consist of one symbol
period (e.g., a duration of one modulation symbol) and one subcarrier, where the symbol
period and subcarrier spacing are inversely related. The number of bits carried by
each resource element may depend on the modulation scheme (e.g., the order of the
modulation scheme). Thus, the more resource elements that a UE 115 receives and the
higher the order of the modulation scheme, the higher the data rate may be for the
UE 115. In MIMO systems, a wireless communications resource may refer to a combination
of a radio frequency spectrum resource, a time resource, and a spatial resource (e.g.,
spatial layers), and the use of multiple spatial layers may further increase the data
rate for communications with a UE 115.
[0052] Devices of the wireless communications system 100 (e.g., network devices 105 or UEs
115) may have a hardware configuration that supports communications over a particular
carrier bandwidth, or may be configurable to support communications over one of a
set of carrier bandwidths. In some examples, the wireless communications system 100
may include network devices 105 and/or UEs 115 that can support simultaneous communications
via carriers associated with more than one different carrier bandwidth.
[0053] Wireless communications system 100 may support communication with a UE 115 on multiple
cells or carriers, a feature which may be referred to as carrier aggregation (CA)
or multi-carrier operation. A UE 115 may be configured with multiple downlink CCs
and one or more uplink CCs according to a carrier aggregation configuration. Carrier
aggregation may be used with both FDD and TDD component carriers.
[0054] In some cases, wireless communications system 100 may utilize enhanced component
carriers (eCCs). An eCC may be characterized by one or more features including wider
carrier or frequency channel bandwidth, shorter symbol duration, shorter TTI duration,
or modified control channel configuration. In some cases, an eCC may be associated
with a carrier aggregation configuration or a dual connectivity configuration (e.g.,
when multiple serving cells have a suboptimal or non-ideal backhaul link). An eCC
may also be configured for use in unlicensed spectrum or shared spectrum (e.g., where
more than one operator is allowed to use the spectrum). An eCC characterized by wide
carrier bandwidth may include one or more segments that may be utilized by UEs 115
that are not capable of monitoring the whole carrier bandwidth or are otherwise configured
to use a limited carrier bandwidth (e.g., to conserve power).
[0055] In some cases, an eCC may utilize a different symbol duration than other CCs, which
may include use of a reduced symbol duration as compared with symbol durations of
the other CCs. A shorter symbol duration may be associated with increased spacing
between adjacent subcarriers. A device, such as a UE 115 or network device 105, utilizing
eCCs may transmit wideband signals (e.g., according to frequency channel or carrier
bandwidths of 20, 40, 60, 80 MHz, etc.) at reduced symbol durations (e.g., 16.67 microseconds).
A TTI in eCC may consist of one or multiple symbol periods. In some cases, the TTI
duration (that is, the number of symbol periods in a TTI) may be variable.
[0056] Wireless communications systems such as an NR system may utilize any combination
of licensed, shared, and unlicensed spectrum bands, among others. The flexibility
of eCC symbol duration and subcarrier spacing may allow for the use of eCC across
multiple spectrums. In some examples, NR shared spectrum may increase spectrum utilization
and spectral efficiency, specifically through dynamic vertical (e.g., across the frequency
domain) and horizontal (e.g., across the time domain) sharing of resources.
[0057] In some wireless communications systems 100, one or more network devices 105 (e.g.,
a donor network device 105, a donor IAB node, a donor base station, etc.) may include
CUs and DUs, where one or more DUs associated with a donor network device may be partially
controlled by a CU associated with the donor network device. The network device CUs
may be a component of a network management function, database, data center, or the
core network 130 (e.g., a 5G NR core network (5GC)). In some cases, the network device
CU may be in communication with the network management function (e.g., in some cases,
the network management function may refer to a separate entity in communication with
the network device CU). In some cases, a network management function may be referred
to as a management function. A network device CU may communicate with a donor network
device 105 via a backhaul link 132 (e.g., a wireline backhaul or a wireless backhaul).
As another example, in IAB networks, a network device CU (e.g., a donor network device
105) may communicate with the core network 130 (e.g., the NGC) via a backhaul link
132 (e.g., a wireline backhaul or wireless backhaul). The donor network device 105
may be referred to, for example in an IAB network, as an IAB donor and may be in communication
with one or more IAB nodes (e.g., other network devices 105) operating as network
device DUs relative to the IAB donor and one or more UEs.
[0058] For example, an IAB network may include a chain of wireless devices (e.g., starting
with the donor network device 105 (a radio access network (RAN) node that terminates
an interface with the core network) and ending with a UE 115, with any number of IAB
nodes or relay network devices in between). IAB nodes (e.g., relay network devices,
relay nodes, relay base stations etc.) may support MT functionality (which may also
be referred to as UE functionality (UEF)) controlled and scheduled by an IAB donor,
or another parent IAB node. IAB nodes (e.g., relay base stations, relay nodes, etc.)
may also support DU functionality (which may also be referred to as access network
functionality (ANF)) relative to additional entities (e.g., IAB nodes, UEs, etc.)
within the relay chain or configuration of the access network (e.g., downstream).
In some cases, MT functionality may refer to an implementation that supports at least
some aspects of a MT or a UE (e.g., as defined by 3GPP TS 23.101 version 8.0.0 Release
8). These relay mechanisms may forward traffic along to the additional entities, extend
the range of wireless access for one or more base stations, enhance the density of
backhaul capability within serving cells, etc.
[0059] Wireless communications system 100 may employ one or more wired and wireless backhaul
links (e.g., backhaul link 132 or backhaul link 134) for establishing connectivity
between a core network (e.g., core network 130) and the one or more wireless nodes
within wireless communications system 100. For example, wireless communications system
100 may include multiple network devices 105 (e.g., base stations, remote radio heads,
etc.), where at least one network device 105 is coupled to a wireline backhaul link,
such as an optical fiber cable. Additional network devices 105 may not be directly
coupled to the core network 130 or to another network device 105 via a wired backhaul
link, and may use wireless backhaul links to communicate backhaul traffic. In such
cases, the network devices 105 may wirelessly communicate backhaul access traffic
to a high-capacity fiber point (e.g., a location where a wireless node is coupled
with a wireline link to core network 130). Each of the backhaul links 132 and 134
may carry packets from the one or more established PDN gateways through the SGi interface
and subsequently direct the packets through the core network and to the coupled wireless
nodes over the S 1 interface.
[0060] While mobile access may sometimes be associated with single-hop communication links
between a source and destination (e.g., an asymmetric link), wireless backhaul communications
may support multi-hop transport and provide robustness through topological redundancy
(e.g., alternative paths for data exchange within a wireless communications network).
Accordingly, underlying links using wireless backhaul communications may be symmetric
in nature and use large-scale resource coordination among the wireless communication
links.
[0061] The relay node multi-connected backhaul manager 101 may transmit, using a first mobile
terminal function of the relay node, a measurement report to a network management
function via a first backhaul link to a first parent node, where the measurement report
includes measurements of a second parent node transmission (e.g., of parent node reference
signal transmission). Further, the relay node multi-connected backhaul manager 101
may receive, via the first backhaul link using the first mobile terminal function
of the relay node, a backhaul link configuration for the second mobile terminal function
based on the transmitted measurement report, and establish a second backhaul link
between the second mobile terminal function of the relay node and the second parent
node based on the received backhaul link configuration. Generally, relay node multi-connected
backhaul manager 101 may be a component, function, or logic of a network device 105
(e.g., a network device 105-a, a network device 105-b, a network device 105-c, etc.).
[0062] The management function multi-connected backhaul manager 102 may receive, by a network
management function via a first backhaul link, a measurement report from a first mobile
terminal function of a relay node, where the measurement report includes measurements
of a second parent node transmission and identify a backhaul link configuration for
the second mobile terminal function based on the received measurement report. Further,
the management function multi-connected backhaul manager 102 may transmit, via the
first backhaul link, the identified backhaul link configuration for the second mobile
terminal function to the first mobile terminal function of the relay node. Generally,
the management function multi-connected backhaul manager 102 may be a component, function,
or logic of core network 130.
[0063] The following two embodiments are falling under the scope of the claimed invention.
The relay node multi-connected backhaul manager 101 exchanges, using a first mobile
terminal function of the relay node, an identifier of the relay node with a first
network management function via a first backhaul link to a first parent node and transmit,
using a second mobile terminal function of the relay node, the same identifier of
the relay node to a second network management function via a second backhaul link
to a second parent node. Further, the relay node multi-connected backhaul manager
101 receives a backhaul link configuration for the second mobile terminal function
based on the transmission of the identifier of the relay node to the first network
management function via the first backhaul link and the transmission of the same identifier
of the relay node to the second network management function via the second backhaul
link.
[0064] The management function multi-connected backhaul manager 102 identifies a relay node
is connected to a first parent node via a first mobile terminal function of the relay
node by exchanging an identifier of the relay node with the first parent node; identify
the relay node is connected to a second parent node via a second mobile terminal function
of the relay node by receiving the identifier of the relay node from the second parent
node, wherein the identification that the relay node is connected to the second parent
node via the second mobile terminal function of the relay node is based at least in
part on the identifier of the relay node from the second parent node being the same
as the identifier of the relay node from the first parent node; and transmit a backhaul
link configuration for the second mobile terminal function based on the identified
relay node connections.
[0065] FIG. 2 illustrates an example of a wireless communications system 200 that supports aspects
of relay nodes with multi-connected cellular backhaul in accordance with one or more
aspects of the present disclosure. In some examples, wireless communications system
200 may implement aspects of wireless communications system 100. Wireless communications
system 200 may support one or more base stations 105 (e.g., which may be examples
of a network device 105 as described in FIG. 1) supporting network access to one or
more UEs 115 within cell coverage areas 110 (e.g., which may be examples of LTEs 115
and coverage areas 110 as described in FIG. 1). In some cases, the one or more cell
coverage areas 110 may be non-collocated. Infrastructure and spectral resources for
NR access within wireless communications system 200 may additionally support wireless
backhaul link 215 capabilities in supplement to wireline backhaul connections 210,
providing an IAB network architecture.
[0066] In some cases, base station 105-a may be split into associated base station CU and
DU entities, where one or more DUs may be partially controlled by an associated CU.
The CU entity of the base station 105-a may facilitate connection between the core
network 205 and the access network (e.g., via a wireline backhaul connection 210 or
wireless connection to the core network). The DUs of the base station 105-a may control
and/or schedule functionality for additional devices (e.g., relay base stations, such
as relay base station 105-b) according to configured wireless backhaul links 215 and
access links 220. Based on the supported entities at the base station 105-a, the base
station 105-a may be referred to as an IAB donor. Relay base station 105-b may support
link connectivity with the IAB donor (e.g., base station 105-a) as part of a relay
chain within the IAB network architecture. For example, base station 105-b may be
split into associated MT and DU entities, where MT functionality of the base station
105-b may be controlled and/or scheduled by a DU entity of base station 105-a (e.g.,
an IAB donor). DUs associated with a base station 105-b may be controlled by MT functionality.
In addition, in some cases, DUs of the base station 105-b may be partially controlled
by signaling messages from CU entities of associated IAB donor nodes of the network
connection (e.g., via an F1-AP). The DU of the base station 105-b may support a serving
cell coverage area 110 of the IAB network coverage area. Based on the supported entities
at the base station 105-b, the base station 105-b may be referred to as a relay base
station, IAB node, relay node, etc.
[0067] Additionally, wireless communications system 100 may employ one or more wireless
access links 220 for establishing mobile access to one or more coupled UEs 115. Each
of the base stations 105 and the UEs 115 may be configured to support cellular RATs,
such as mmW-based RATs, for access traffic between the UEs 115 and the base stations
105. Moreover, each of base stations 105 may share resources of the configured RATs
for access traffic with backhaul traffic over the network (e.g., as in the case of
IAB). IAB network solutions may be increasingly beneficial with the evolution of cellular
technologies due to enhancements in wireless link capacity. Specifically, IAB network
solutions may provide solutions to densification of network cells (i.e., cost reduction
of small cell deployments) and increases in data traffic, as a means to maximize spectrum
efficiency through joint optimization and integration of access and backhaul resources
within the network. IAB network solutions may be particularly suitable for mmW RATs
due to a large bandwidth per channel and the need to mitigate short term signal blocking.
[0068] An access link using a mmW-based RAT may be designed as an asymmetric single-hop
link, which may be used for assigning control and scheduling tasks to base stations
105 while providing instruction to one or more UEs 115 for scheduling communication.
In such cases, base stations 105 may coordinate wireless resources among multiple
UEs 115, while each UE 115 may be assigned to one base station 105 at a time. In some
cases, inter-node links may be symmetric in nature and may form mesh topologies for
enhanced robustness, where wireless transport may occur along multiple hops.
[0069] Communication according to a particular RAT (e.g., mmW RAT) over an IAB network may
enable one or more functionalities at the base stations 105 of the network. For example,
each base station 105 may be configured for ANF and UEF to allow each base station
105 to act as a scheduling entity and a receiving (e.g., scheduled) entity. Each of
the functionalities may be operated via each of the one or more backhaul links 215.
ANF may enable the respective base stations 105 to operate as a scheduling entity
over one or more access links 220, and communicate with one or more UEs 115 located
within the IAB network. ANF may further enable the respective base stations 105 to
operate as a scheduling entity over one or more coupled backhaul links 215, to facilitate
communication between the one or more other base stations 105 of the IAB network (i.e.,
via the mesh topology). UEF functionality may enable the respective base station 105
to operate as a scheduled entity and communicate with one or more other base stations
105 to receive data. The combination of the UEF and ANF capability at each base station
105 of the IAB network may allow each of the base stations 105 to utilize switching
operations over the wireless spectrum associated with the RAT, to transmit access
traffic to/from UEs 115 and backhaul traffic to/from core network 130 providing coupled
access to the one or more PDNs. Additionally, each of base stations 105 may include
a routing table for examining a received data packet and forwarding the packet along
the best path of the IAB network toward the specified IP address of the packet's destination.
[0070] Wireless communications system 200 may illustrate an example of a densified small
cell system integrating access and backhaul links (e.g., allowing for self-backhauling
of access traffic). Integrating access and backhaul links (e.g., integrating wireless
backhaul links 215) may allow for such densified small cell systems, without the need
for each cell (e.g., each base station 105) to be connected to a fiber point or wireline
backhaul connection 210. Wireless communications system 200 may thus illustrate a
multi-hop wireless backhaul network (e.g., with self-backhauling). Such densified
small cell systems may provide for sub-6 frequencies which may, for example, provide
for massive-MIMO technologies to improve spectral efficiency. In some cases, each
relay base station 105 may be associated with a single MT function, and may thus employ
backhaul relaying as shown. In some cases, relay base stations 105 may support multiple
MT functions, in which case relay base stations 105 may be capable of multi-connected
cellular backhaul (e.g., as described herein, for example, with reference to FIG.
3).
[0071] FIG. 3 illustrates an example of a wireless communications system 300 that supports relay
nodes with multi-connected cellular backhaul in accordance with one or more aspects
of the present disclosure. In some examples, wireless communications system 300 may
implement aspects of wireless communications system 100 and wireless communications
system 200, as described with reference to FIGs. 1 and 2. For example, FIG. 3 illustrates
a wireless communications system 300 (e.g., a NR system) that supports sharing of
infrastructure and spectral resources for NR access with wireless backhaul link capabilities,
in supplement to wireline backhaul connections, providing an IAB network architecture.
Wireless communications system 300 may include a core network 305 (e.g., NGC), and
base stations or supported devices split into one or more support entities (e.g.,
functionalities) for promoting wireless backhaul density in collaboration with NR
communication access. Aspects of the supporting functionalities of the base stations
may be referred to as IAB nodes.
[0072] Wireless communications system 300 may include an IAB donor node split into associated
base station CU 310 and DU 315 entities, where DUs 315 associated with the IAB donor
node may be partially controlled by the associated CU 310. CUs 310 of IAB donor nodes
may host layer 3 (L3) (e.g., RRC, service data adaption protocol (SDAP), PDCP, etc.)
functionality and signaling. Further CUs 310 of IAB donor nodes may communicate with
core network 305 over, for example, an NG interface (which may be an example of a
portion of a backhaul link). DUs 315 may host lower layer, such as layer 1 (L1) and
layer 2 (L2) (e.g., RLC, MAC, PHY, etc.) functionality and signaling. A DU 315 entity
of an IAB donor node may support one of multiple serving cells of the network coverage
according to connections associated with backhaul and access links of the IAB network.
DUs 315 of the IAB donor node may control both access links and backhaul links within
the corresponding network coverage and may provide controlling and scheduling for
descendant (e.g., child) relay IAB nodes 320 and/or UEs 115.
[0073] Relay IAB nodes 320 may be split into associated MT and DU entities. MT functionality
(e.g., UEF) of the relay IAB nodes 320 may be controlled and/or scheduled by antecedent
IAB nodes (e.g., by an IAB donor or another IAB node as its parent node) of the established
connectivity via access and backhaul links of a coverage area. DUs associated with
a relay IAB node 320 may be controlled by MT functionality of the node. In addition,
DUs of the IAB nodes 320 may be partially controlled by signaling messages from CU
310 entities of associated IAB donor nodes of the network connection (e.g., via an
F 1-AP). The DUs of the IAB nodes 320 may support one of multiple serving cells of
the network coverage area. DU functionality (e.g., ANF) may schedule child IAB nodes
and UEs, and may control both access links and backhaul links under its coverage.
[0074] Each relay node may include at least one MT function and one DU. The relay may connect
to a parent relay node or a donor node via each MT function, and may further support
connections to UEs 115 and child relay nodes via the DU. In some cases, all DUs on
relay nodes and donor nodes may be connected to a centralized donor CU (e.g., CU 310),
which may hold a network management function, or be connected to a network management
function. The network management function may support link management, route management,
topology management, resource management, etc. for the wireless communications system
300 (e.g., the IAB network). The connection between DUs across wireless backhaul links
may use a modified form of the F1 protocol (e.g., F1
∗). Each relay node MT function may include a RRC connection to the CU 310. Further,
each relay node DU may include a F1
∗ control plane connection to the CU 310. In this manner, the network management function
may support link configuration, route configuration, and resource configuration tasks
for the wireless backhaul topology.
[0075] Wireless communications system 300 may employ relay chains for communications within
the IAB network architecture. For example, an IAB donor may support a primary backhaul
link and one or more secondary (e.g., parallel or backup) backhaul links to relay
IAB nodes 320. The IAB donor may further support one or more access links to additional
devices (e.g., UEs 115) or entities of the network. In addition, MT functionality
of each of the one or more relay IAB nodes 320 and UEs 115 may be configured to support
network connectivity to multiple parent nodes via access and backhaul links associated
with coverage areas of the IAB network.
[0076] For a relay IAB node to support multiple paths to the CU 310, the relay IAB node
may hold multiple MT functions (e.g., multiple MTs). For example, relay IAB node 320-a
may support a single MT function (e.g., and may have a single path, or backhaul link,
to CU 310), relay IAB node 320-b may support two MT functions (e.g., and may have
two paths, or two backhaul links, to CU 310), and relay IAB node 320-d may support
a three MT functions (e.g., and may have three paths, or three backhaul links, to
CU 310). In cases where a relay IAB node 320 supports multiple MT functions, each
MT function may support connectivity to a different parent node. For example, for
IAB relay node 320-b, a first MT function may establish a first backhaul link through
a first parent node (e.g., DU 315-a) and a second MT function may establish a second
backhaul link through a second parent node (e.g., DU 315-b). As another example, for
IAB relay node 320-d, a first MT function may establish a first backhaul link through
a first parent node (e.g., IAB node 320-a), a second MT function may establish a second
backhaul link through a second parent node (e.g., DU 315-a), and a third MT function
may establish a third backhaul link through a third parent node (e.g., IAB node 320-c,
and eventually through DU 315-a or DU 315-b after relay by IAB node 320-c).
[0077] In such a manner, IAB nodes supporting multiple MT functions may support topological
redundant paths in the wireless communications system 300. In some cases, a network
management function (e.g., associated with CU 310) may configure multiple paths (e.g.,
multiple backhaul links) to be used in parallel or simultaneously (e.g., such as for
relay IAB node 320-b). As discussed herein, use of parallel or simultaneous backhaul
links may refer to operation of backhaul links in conjunction with each other (e.g.,
whether using each link for redundant communication of backhaul information, using
each link for load balancing of backhaul information, etc.). As such, parallel backhaul
link operation may refer backhaul links being active and available for backhauling,
and may not necessarily imply both backhaul links must convey the same information
at the same instance in time. In other cases, the network management function (e.g.,
associated with CU 310) may configure backup paths (e.g., or backup backhaul links)
to be used in cases where the established backhaul link deteriorates, or an improved
backhaul link is identified by the IAB relay node or network management function.
For example, relay IAB node 320-c may backhaul communications through DU 315-b, but
may be configured (e.g., by the network management function) with a backup backhaul
link through DU 315-a. For example, the network management function may configure
multiple MT function of a relay node to connect to different parent nodes to simultaneously
use all link (e.g., backhaul links) the relay node has with its multiple parents,
or the network management function may configure the relay node to only use a subset
and keep the other links for backup purposes (e.g., shown as dotted lines).
[0078] Multi-path connectivity via such multiple backhaul links may provide robustness to
radio link failure on backhaul links (e.g., on deteriorating backhaul links). Further,
capacity optimization though load balancing across the multiple backhaul paths may
also be realized (e.g., to increase backhaul throughput, reduce latency associated
with backhaul over a single backhaul link, etc.). In order for a network management
function to coordinate and configure multiple backhaul links (e.g., for relay nodes
supporting multiple MT functions), the management function may first become away that
a relay node supports such multiple MT functionality (e.g., and is therefore capable
of multi-connected cellular backhaul).
[0079] Multiple MT functions residing on one relay node may have different properties (e.g.,
different MT functions of a relay node may cover different angular sectors, support
different frequency bands, have different power levels, etc.). Further, MT functions
and DUs residing on the same relay node may have a relationship with each other (e.g.,
an MT and a DU may share a same antenna panel). Further, multiple MTs with different
antenna panels may have limited antenna isolation, which may affect resource allocation
for simultaneous (e.g., parallel) operation. To take full advantage of the multitude
of MTs collocated on a relay (e.g., to maximize backhaul efficiency in wireless communications
system 300), the network management function may be made aware of such aspects, and
may have a means to configure multi-MT utilization accordingly.
[0080] A first MT function of a relay IAB node (e.g., relay IAB node 320-d) may establish
a backhaul link with a first parent (e.g., IAB node 320-a) and transmit a list of
MT-identifiers for the MTs supported (e.g., identification of the MT function(s) supported)
to a network management function (e.g., via a first backhaul link to IAB node 320-a).
In this manner, each MT function may be individually addressed by the network management
function. In some cases, the relay IAB node 320-d may provide further details on the
capabilities of each MT, inter-MT relations, etc. In some examples, the network management
function may transmit a measurement configuration, to the first MT of IAB node 320-d
via the first backhaul link, for a second MT function of IAB node 320-d. For example,
the measurement configuration may include an identifier of the second MT function,
one or more parent nodes to be measured by the second MT function, measurements to
be received (e.g., RSSI, RSRP, etc.), etc. The second MT function of the IAB node
320-d may perform the measurements (e.g., of the indicated parent node(s), or of all
detected parent nodes), and the IAB node 320-d may transmit a measurement report (e.g.,
including measurements received by the second MT function of the IAB node 320-d) to
the network management function (e.g., via the first backhaul link to IAB node 320-a).
That is, the MT functions of an IAB node may be in communication with each other (e.g.,
the first MT function of IAB node 320-d may pass the measurement configuration to
the second MT function of IAB node 320-d, and the second MT function of IAB node 320-d
may pass the measurement results, or measurement report, back to the first MT function
of IAB node 320-d (e.g., for the first MT function to transmit to the network management
function).
[0081] The network management function may then select a second parent node (e.g., for a
second backhaul link with the second MT function of IAB node 320-d) based on the received
measurement report. The network management function may transmit a configuration for
a second link to the second MT to IAB node 320-d over the first backhaul link (e.g.,
via the first MT of IAB node 320-d). The second MT of IAB node 320-d may then establish
a second backhaul link (e.g., to the network management function through IAB node
320-c) based on the received backhaul link configuration.
[0082] In other examples, MT functions of IAB nodes may establish links with parent nodes
autonomously (e.g., according to IAB node settings, without configuration from a parent
node or network management function, etc.). In such cases, a first MT function of
a relay IAB node (e.g., relay IAB node 320-d) may establish a first backhaul link
with a first parent (e.g., IAB node 320-a) and may establish a relay identifier (e.g.,
an identifier of the relay IAB node 320-d) with the network management function (e.g.,
through the first backhaul link). A second MT function of the relay IAB node 320-d
may conduct signal strength measurements of other parent nodes (e.g., DU 315-a, IAB
node 320-b, IAB node 320-c, etc.) and select a second parent node (e.g., IAB node
320-c) based on a parent-selection policy (e.g., criteria of the IAB node 320-a for
parent selection, such as the strongest detected parent node, a parent node with a
signal strength above a threshold, etc.). The IAB node 320-d may then connect to the
second parent node, IAB node 320-c, and transmit the relay identifier to the network
management function through the second backhaul link to IAB node 320-c. As such, the
network management function may associate the second MT function with the same relay
node as the first MT function (e.g., by comparing the relay identifiers received over
each backhaul link, identifying the two relay identifiers are associated with a single
relay node, etc.). The network management function may then transmit (e.g., via the
first backhaul link to the first MT function) a configuration for the second link
from a second MT function to a second parent (IAB node 320-c). The second MT function
may establish the second link and use it for backhauling (e.g., in accordance with
the backhaul link configuration).
[0083] Additional detail of the options for handling awareness and coordinated configuration
of multi-MT relay nodes described above are discussed in more detail below. For example,
in one scenario the management function may have explicit awareness and control over
multi-MT operation (e.g., as described in more detail below with reference to FIGs.
4 and 5). In another scenario, the relay node may autonomously establish multi-MT
connectivity based on preconfigured parent-selection policies (as described in more
detail below with reference to FIGs. 6 and 7). In either case, the network management
function may configure backhaul routes (e.g., backhaul links) and resource configuration
across the redundant topology.
[0084] In either scenario (e.g., whether the management function has explicit awareness
and control over multi-MT operation or the relay node autonomously establishes multi-MT
connectivity), signaling messages between the MT functions of the relay node and the
network management function (e.g., such as MT capability reports transmitted by a
relay node, measurement configurations transmitted by a network management function,
measurement reports transmitted by a relay node, backhaul link configurations transmitted
by a network management function, etc.) may, in some cases, use RRC signaling. In
some cases, signaling messages between the MT functions of the relay node and the
network management function may use F 1 protocol or non-access stratum (NAS) protocols.
In some examples, the links may use cellular RATs (e.g., such as NR or LTE). In some
examples, the relay node may also hold a full base station (e.g., a full gNB) rather
than solely a DU (e.g., a gNB-DU). The relay node may also hold an eNB, or a DU of
an eNB, which may be connected via the multi-hop wireless backhaul with a CU of an
eNB. In some cases, the wireless links between relay node and parent nodes may include
a RLC channel. The RLC channel may include an adaptation layer, which may be used,
for example, for routing.
[0085] In some examples, any communication between the network management function and a
second MT of the relay node via the first MT of the relay node may occur via a container
(e.g., or field) inserted into a message between the network management function and
the first MT. In some cases, communication between the network management function
and a second MT of the relay node via the first MT (e.g., the container) may include
an identifier of the second MT. In some cases, the configuration of routes, route
utilization, link utilization, and resource allocation among multiple upstream links
supported by a relay node may be decided and configured by the network management
function. The network management function may be a part of a gNB, gNB-CU, eNB, eNB-CU,
or a core network (e.g., such as an EPC or NGC). In some cases, the network management
function may be collocated with these nodes or functions. In some cases, the network
management function may have an interface to these nodes or functions. In some cases,
the interface to these nodes or functions may be transparent to the MTs communicating
with the network management function.
[0086] FIG. 4 illustrates an example of a flowchart 400 that supports relay nodes with multi-connected
cellular backhaul in accordance with one or more aspects of the present disclosure.
In some examples, flowchart 400 may implement aspects of wireless communications system
100, wireless communications system 200, and/or wireless communications system 300.
For example, flowchart 400 may illustrate operations of a network management function
and a relay node (e.g., an intermediary IAB node), as described with reference to
FIGs. 1 through 3. Specifically, flowchart 400 may illustrate a network management
function having explicit awareness and control over multi-MT operation. As discussed,
mechanisms for performing one or more processes of the described techniques may be
performed by a network management function, as well as a first MT function or first
MT entity (e.g., a UEF) and a second MT function or second MT entity of a relay node.
However, the described techniques may be extended to additional MT functions supported
by a relay node by analogy, without departing from the scope of the present disclosure.
[0087] At 405, a relay node may, using a first MT function, select a first parent node (e.g.,
a parent relay node, a DU of a donor node, etc.) based on a parent selection policy.
For example, the parent selection policy may be identified in system information,
may be preconfigured on the relay node, etc. In some cases, the relay node may connect
to the network once to retrieve the parent selection policies from operations, administration,
and maintenance (OAM) functions, or other sources.
[0088] At 410, the first MT function of the relay node may establish a first link (e.g.,
a first backhaul link) to the selected parent node.
[0089] At 415, the first MT function may transmit a signaling message to the network management
function. The message may include a relay identifier (e.g., an identification of the
relay node) and list of MT-identifiers of MTs supported by the relay node (e.g., identification(s)
of one or more of the supported MT functions). As such, each MT may be individually
addressed by the management function. Alternatively, the first MT may send a relay
identifier and the number of MTs supported. In this case, the relay identifier along
with the MT index may allow for the network management function to still uniquely
identify the MTs (e.g., using a combination of the relay identifier and the MT index).
In some cases, the relay identifier may be assigned by the network (e.g., by the network
management function), and the MT may provide the number of MTs supported.
[0090] The first MT may provide details on the capabilities of each MT (e.g., RATs, frequency
bands, power class, angular coverage range in azimuth and elevation direction, number
of antenna panels supported, etc.). For example, the first MT may transmit a capability
report (e.g., including capabilities of each supported MT function) to the network
management function via the first backhaul link. Such may enable the network management
function to process and understand the limitations of the relay node for multi-MT
operation. In some cases, the first MT may further provide details on inter-MT relation
(e.g., such as inter-MT antenna isolation, azimuth or elevation range overlap, etc.).
In some cases, the first MT may further provide details on the number of DUs supported
by the relay, may provide relation between MTs and DUs (e.g., if an MT shares an antenna
panel with a DU), etc. The first MT may provide some or all of such information, for
example, via RRC to the network management function.
[0091] At 420, the relay node may use the first wireless link for backhauling access or
backhaul traffic of collocated DUs.
[0092] At 425, the network management function may decide to activate an additional MT function
(e.g., a second MT function) of the relay node and may select a parent of the second
MT function. The network management function may convey such to the relay node by
transmitting a measurement configuration message to the first MT, which may define
measurement events to be reported by the second MT (e.g., to the network management
function via the first MT of the relay node). The measurement configuration message
may specify a measurement configuration explicitly for a specific MT (e.g., by including
an MT identifier or MT index in the configuration). Alternatively, configurations
may implicitly apply to all or a subset of the MTs supported by the relay node. The
subset of MTs may also, in some cases, be specified in the configuration message.
[0093] At 430, the second MT may conduct measurements based on the measurement configuration
and upon an event trigger. The first MT may report the measurements (e.g., performed
by the second MT) to the management function (e.g., to the gNB-CU) while indicating
the second MT has conducted the measurement. In some cases, the measurement configuration
may be transmitted via RRC.
[0094] At 435, the network management function may (e.g., based on the measurement report)
decide to activate the second MT and may select a second parent relay, under the control
of the network management function, for the second MT. The network management function
may transmit a signaling message (e.g., a backhaul link configuration message) to
the first MT with a configuration for the second MT. The configuration for the second
MT may include an identifier for the second MT, as well as other link and route configuration
information for the second MT. In some cases, the configuration may use RRC (e.g.,
the backhaul link configuration may be transmitted in a RRC Reconfiguration message).
[0095] At 440, the second MT may establish a link as specified in the backhaul link configuration
message. In some cases, as part of the link establishment, the second MT may authenticate
at the network. The second MT may further report capabilities in the same or similar
manner as the first MT reported its capabilities.
[0096] At 445, based on the backhaul link configuration, the relay node may then use the
second wireless link for backhauling of access or backhaul traffic of collocated DUs,
or it may further use both wireless links simultaneously for the backhauling of access
or backhaul traffic of collocated DUs. The backhaul link configuration may further
specify for the relay node to use the first link for one subset of collocated DUs
and the other link for another subset of collocated DUs.
[0097] FIG. 5 illustrates an example of a process flow 500 that supports relay nodes with multi-connected
cellular backhaul in accordance with one or more aspects of the present disclosure.
In some examples, process flow 500 may implement aspects of wireless communications
system 100, wireless communications system 200, and/or wireless communications system
300. For example, process flow 500 may include a relay node 505, a parent node 510-a,
a parent node 510-b, and a CU 310-a, which may be examples of corresponding functionality
of an IAB network architecture (e.g., such as a network device 105 or base station
105, relay node 320, DU 315, CU 310), as described with reference to FIGs. 1 through
4. Process flow 500 may illustrate a network management function becoming aware of
multi-MT support by a relay node (e.g., relay node 505), as well as network management
function control over multi-MT operation (e.g., operation of MT 515-a and MT 515-d).
In the following description of the process flow 500, the operations between the relay
node 505, parent nodes 510, and a network management function (e.g., CU 310-a, or
some network management function or network management function entity in communication
with CU 310-a) may be transmitted in a different order than the exemplary order shown,
or the operations performed by relay node 505, parent node 510-a, parent node 510-b,
and the network management function may be performed in different orders or at different
times. In some cases, certain operations may also be left out of the process flow
500, or other operations may be added to the process flow 500.
[0098] Process flow 500 may illustrate a relay node 505 in communication with a network
management function via a first wireless backhaul link between a first MT function
(e.g., MT 515-a) and a first parent or control node (e.g., parent node 510-a). Process
flow 500 further illustrates network management function configuration of a second
wireless backhaul link (e.g., using the multiple MT functionality of the relay node
505) between a second MT function (e.g., MT 515-d) and a second parent or control
node (e.g., parent node 510-b). That is, parent node 510-a and parent node 510-b may
each refer to either a parent relay node (e.g., which may include both MT functionality
and a DU 520) or a donor node (e.g., which may include a DU 520 and may be directly
connected to CU 310-a, or in some cases may include CU 310-a). In cases where parent
node 510-a and/or parent node 510-b refer to a parent relay node, the parent relay
node may include MT functionality that may further relay to, or serve as a midpoint
in the link to, a donor node. That is, parent node 510-a and parent node 510-b may
each refer to a parent node of relay node 505, and may refer to a parent relay node
or a donor node, as described herein, and may each provide a link from relay node
505 to a network management function (e.g., CU 310-a).
[0099] DU 520-a associated with a relay node 505 may be partially controlled and/or scheduled
by MT 515-a and/or MT 515-d. DU 520-a may host lower layer, such as L1 and L2 (e.g.,
RLC, MAC, PHY, etc.), functionality and signaling. Relay node 505 may be a descendant
(e.g., child) node relative to parent node 510-a and parent node 510-b along two different
paths within the relay chain. Further, relay node 505 may include MT 515-a, which
may be controlled and/or scheduled by DU 520-b of parent node 510-a via access and
backhaul links of the IAB network, and may further include MT 515-d, which may be
controlled and/or scheduled by DU 520-c of parent node 510-b via access and backhaul
links of the IAB network. In addition, in some cases (e.g., when parent node 510-a
and parent node 510-b are both parent relay nodes), DU 520-b and DU 520-c may be partially
controlled and/or scheduled by signaling messages from a CU 310-a of an IAB donor
(e.g., via an F1-AP). Parent node 510-a may support one or more wireless backhaul
and/or access links within the relay chain, providing network services to one or more
descendant devices throughout the network (e.g., such as relay node 505). Parent node
510-b may support one or more wireless backhaul and/or access links within the relay
chain, providing network services to one or more descendant devices throughout the
network (e.g., such as relay node 505).
[0100] At 505, relay node 505 may establish a first backhaul link (BL) between the first
MT function (e.g., MT 515-a) and a first parent node (e.g., parent node 510-a). In
some cases, the first backhaul link may be established based on the relay node 505
measuring, using the MT 515-a, one or more parent nodes, and selecting parent node
510-a based on a parent-selection policy. The first backhaul link may connect relay
node 505 (e.g., specifically MT 515-a) to a network management function (e.g., CU
310-a) through parent node 510-a. As discussed above, in some cases, parent node 510-a
may be a parent relay node, or a DU associated with a donor node. That is, parent
node 510-a may generally refer to a first node, in communication with relay node 505,
under the control of the management control function, or CU 310-a.
[0101] At 510, relay node 505 may transmit, via the first backhaul link using MT 515-a,
a capability report to the network management function. The capability report may
include capabilities of the relay node in terms of MT functionality (e.g., a number
of MT functions supported, identifiers of the MTs supported, isolation between different
MT functions, etc.) as well as capabilities of individual MT functions (e.g., such
as RATs supported by a second MT function, frequency bands supported by the second
MT function, azimuth and elevation patterns supported by the second MT function, etc.).
For example, the capability report may include an identifier of MT 515-d, one or more
RATs supported by MT 515-d, one or more frequency bands supported by MT 515-d, azimuth
and elevation patterns supported by MT 515-d, RF capabilities of MT 515-d, isolation
between MT 515-a and MT 515-d, an identifier of the relay node 505, a list of supported
MT functions (e.g., identifiers of MT 515-a, MT 515-d, and any other MTs supported
by relay node 505), etc.
[0102] At 515, the network management function may identify a measurement configuration
for MT 515-d based on the received capability report. For example, the network management
function may consider the capabilities of relay node 505 (e.g., and MT 515-d) and
may identify parent nodes (e.g., parent node 510-b) for the MT 515-d to measure. In
general, the measurement configuration may include identification of MT functions
to perform measurements, identification of parent nodes to be measured, identification
of measurements to be taken (e.g., RSSI measurements, RSRP measurements, etc.), etc.
For example, in cases where relay node 505 indicates several MT functions (e.g., more
than two MT functions) in the capability report, the measurement configuration may
identify parent nodes to be measured and measurements to be received by more than
one MT. The measurement configuration may indicate (e.g., via an MT identifier, that
may have been included in the capability report) which MT functions are to perform
measurements, which measurement are to be performed, which parent nodes each MT function
should measure, etc.
[0103] At 520, the network management function may transmit, via the first backhaul link,
the identified measurement configuration to the MT 515-a.
[0104] At 525, the relay node may perform, using MT 515-d, one or more measurements of parent
node 510-b according to the measurement report received at 520. For example, MT 515-a
may receive the measurement configuration and may pass the measurement configuration
to MT 515-d (e.g., as the MT 515-a and MT 515-d may be connected and in communication
within the relay node 505). The relay node 505 may thus perform, using MT 515-d, measurements
of parent node 510-b based at least in part on the measurement configuration.
[0105] At 530, the relay node may transmit a measurement report, including the measurement
information received by MT 515-d, to the network management functions via the first
backhaul link to parent node 510-a. For example, MT 515-d may perform measurements
and pass measurement reporting information to MT 515-a (e.g., as the MT 515-d and
MT 515-a may be connected and in communication within the relay node 505), and the
MT 515-a may transmit the measurement report to parent node 510-a.
[0106] At 535, the network management function may identify a backhaul link configuration
(e.g., for the relay node 505 via MT 515-d) based at least in part on the measurement
report received at 530. For example, the network management function may identify
which parent node(s) additional MTs of the relay node should connect to, whether the
additional backhaul links will be operated in parallel with the first backhaul link,
as a backup to the first backhaul link, etc. In some cases, the network management
function may determine second backhaul link route utilization information, second
backhaul link utilization information, second backhaul link resource allocation information,
etc. based on the received measurement report.
[0107] At 540, the network management function may transmit, via the first backhaul link,
the identified backhaul link configuration for the MT 515-d to the MT 515-a (e.g.,
via parent node 510-a). In some cases, the backhaul link configuration may include
information regarding second backhaul link establishment and operation (e.g., identification
of a second parent node to connect to, route utilization information, link utilization
information, resource allocation information, etc.).
[0108] At 545, the network management function may optionally transmit a routing configuration,
indicating how the first backhaul link and the second backhaul link should be used
(e.g., in parallel, as primary and backup backhaul links, etc.). In some cases, the
routing configuration information may be included in the backhaul link configuration
transmitted at 540 (e.g., in some cases, the information of 545 may be included in
540, and not as a separate message or transmission).
[0109] At 550, MT 515-d may establish a second backhaul link between the second MT function
(e.g., MT 515-d) and the second parent node (e.g., parent node 510-b). The second
backhaul link may connect relay node 505 (e.g., specifically MT 515-d) to a network
management function (e.g., CU 310-a) through parent node 510-b. As discussed above,
in some cases parent node 510-b may be a parent relay node, or a DU associated with
a donor node. That is, parent node 510-b may generally refer to a first node, in communication
with relay node 505, under the control of the management control function, or CU 310-a.
[0110] As such, relay node 505 may operate in a multi-connected cellular backhaul state
(e.g., with multiple backhaul connections to the network management function). The
network management function may coordinate the multiple backhaul links associated
with relay node 505. For example, a routing configuration (e.g., of 545) may update
or reconfigure the first and/or second backhaul link such that the usage of one or
both of the first and second backhaul links may be dynamically adjusted by the network
management function (e.g., according to changing conditions of the backhaul links,
changing conditions of the amount or priority of backhaul traffic, etc.).
[0111] FIG. 6 illustrates an example of a flowchart 600 that supports relay nodes with multi-connected
cellular backhaul in accordance with one or more aspects of the present disclosure.
In some examples, flowchart 600 may implement aspects of wireless communications system
100, wireless communications system 200, and/or wireless communications system 300.
For example, flowchart 600 may illustrate operations of a network management function
and a relay node (e.g., an intermediary IAB node), as described with reference to
FIGs. 1 through 3. Specifically, flowchart 600 may illustrate autonomous establishment
of multi-MT connectivity based on preconfigured parent-selection policies, and network
management function coordinated backhaul configuration (e.g., in cases where multiple
MT functions associated with a same relay node autonomously connect to a same network
management function over two or more backhaul links). As described, mechanisms for
performing one or more processes of the described techniques may be performed by a
network management function, as well as a first MT function or first MT entity (e.g.,
a UEF) and a second MT function or second MT entity of a relay node. However, the
described techniques may be extended to additional MT functions supported by a relay
node by analogy, without departing from the scope of the present disclosure.
[0112] At 605, a relay node may, using a first MT function, select a first parent node (e.g.,
a parent relay node, a DU of a donor node, etc.) based on a parent selection policy.
For example, the relay node may identify the parent selection policy in system information.
In other cases, the parent selection policy may be preconfigured. In some cases, the
relay node may connect to the network once to retrieve the parent selection policies
from OAM functions, or other sources.
[0113] At 610, the first MT function of the relay node may establish a first link (e.g.,
a first backhaul link) to the selected parent.
[0114] At 615, the first MT function of the relay node may send a relay identifier (e.g.,
an identifier of the relay node) to the network management function during the link
establishment procedure. In some cases, the relay identifier may be provided by the
network (e.g., the network management function may establish the relay identifier,
and may inform the relay node of its relay identifier during the link establishment
procedure). In some examples, the first MT may further transmit capabilities of additional
MTs (e.g., in a capabilities report including a number of MTs supported, capabilities
of the MTs, etc., as described herein) of the relay node to the network management
function. In some cases, the relay identifier and/or the capabilities report may be
transmitted using an RRC message. In some cases, the first MT function may receive,
from the network management function, a policy or a request for the activation of
further MTs.
[0115] At 620, The relay node may use the established first wireless link for the backhauling
of access of backhaul traffic of collocated DUs.
[0116] At 625, using a second MT function, the relay node may measure and select a second
parent relay node (e.g., based on parent-selection policies). The relay node may then
establish a second backhaul link with the selected parent node. In some cases, the
measurements (e.g., and selection) may be based on signal strength (e.g., of measurements
associated with the different parent nodes). In some cases, the parent-selection policies
used by the second MT function may be different than parent-selection policies used
by the first MT.
[0117] At 630, The second MT function of the relay node may establish a second backhaul
link to the selected parent node.
[0118] At 635, during the link establishment procedure, the second MT function may send
the relay identifier to the network management function (e.g., the resource management
function). In some cases, the second MT function may transmit the relay identifier
using RRC signaling.
[0119] If the same network management function supports both parents, the network management
function may derive or identify that the first MT and second MT reside on the same
relay node, and may further identify that the relay node is thus dual-connected. For
example, the network management function may receive the relay identifier, from the
first MT function, over the first backhaul link and may also receive the relay identifier,
from the second MT function, over the second backhaul link. As such, the network management
function may determine that the two received relay identifiers are associated with
the same relay node, and that the relay node is thus dual-connected, via two MT functions
of the relay node, over two backhaul links to the network management function.
[0120] The network management function may therefore be capable of performing further configuration
operations for each MT function of the relay node. For example, the network management
function may configure which MT function of the relay node carries traffic, whether
the two backhaul links are to be used in parallel, whether one backhaul link is to
be reserved as a backup backhaul link, etc. In some cases, each MT function may (e.g.,
at 610 and 630) send their respective MT identifiers during link establishment. In
such cases, the network management function may include an identifier of the MT function,
of which it is configuring, in the configuration sent to the MT. As such, for example,
the network management function may transmit a configuration for the second MT (e.g.,
by including the second MT function identifier in the backhaul link configuration
message) over the first link, and the relay node may identify the backhaul link configuration
is for the second MT function.
[0121] In scenarios where different network management functions support the two parent
nodes (e.g., different management functions support the first and second parent nodes
that the relay node autonomously connected to), each of the network management functions
may consider the relay node single-connected. As such, each of the network management
functions may perform further configuration operations for one of the two MT functions.
To avoid conflicting configuration, such as same resource assignment for both links,
the MT function may provide different capabilities (e.g., such as different bands
supported) on each link. In some cases, the MT may also use one of the links as a
backup link only. Further, the relay node may also identify or differentiate if the
MT functions are connected to the same or different network management functions (e.g.,
if the two parent nodes that the relay node's two MT functions are connected to are
supported by the same or different network management functions). For this purpose,
the topology and resource management function may provide its own identifier (e.g.,
a network management function identifier or a network identifier) to each respective
MT function of the relay node. The relay node may then compare the network management
function identifiers received over each of its MT functions, and identify or determine
whether the relay node is dual-connected to a single network management function (e.g.,
if the network identifiers indicate a same network management function) or single-connected
to two network management functions (e.g., if the network identifiers indicate different
network management functions).
[0122] At 640, based on configuration received at 635, the relay node may then use the second
wireless link for the backhauling of access traffic or backhaul traffic of collocated
DUs, or the relay node may use both wireless links simultaneously (e.g., in parallel)
for the backhauling of access or backhaul traffic of collocated DUs. In some cases,
the configuration may further specify whether the relay node is to use the first link
for one subset of collocated DUs and the other link for another subset of collocated
DUs (e.g., in some cases, the configuration may divide backhauling over the two backhaul
links by assigning backhaul of certain collocated DUs to each link).
[0123] FIG. 7 illustrates, falling under the scope of the claimed invention, an example of a process
flow 700 that supports relay nodes with multi-connected cellular backhaul in accordance
with one or more aspects of the present disclosure. In some examples, process flow
700 may implement aspects of wireless communications system 100, wireless communications
system 200, and/or wireless communications system 300. For example, process flow 700
may include a relay node 705, a parent node 710-a, a parent node 710-b, and a CU 310-b,
which may be examples of corresponding functionality of an IAB network architecture
(e.g., such as a network device 105 or a base station 105, relay node 320, DU 315,
CU 3 10), as described with reference to FIGs. 1 through 4. Process flow 700 may illustrate
a network management function becoming aware of multi-MT support by a relay node,
as well as network management function control over multi-MT operation. In the following
description of the process flow 700, the operations between the relay node 705, parent
nodes 710, and a network management function (e.g., CU 310-a, or some network management
function or network management function entity in communication with CU 310-a) may
be transmitted in a different order than the exemplary order shown, or the operations
performed by relay node 705, parent node 710-a, parent node 710-b, and the network
management function may be performed in different orders or at different times. In
some cases, certain operations may also be left out of the process flow 700, or other
operations may be added to the process flow 700.
[0124] At 705, relay node 705 may (e.g., autonomously) establish a first backhaul link between
the first MT function (e.g., MT 715-a) and a first parent node (e.g., parent node
710-a). In some cases, the first backhaul link may be established based on the relay
node 705 measuring, using the MT 715-a, one or more parent nodes, and selecting parent
node 710-a based on a parent-selection policy. The first backhaul link may connect
relay node 705 (e.g., specifically MT 715-a) to a network management function (e.g.,
CU 310-b) through parent node 710-a. As discussed above, in some cases parent node
710-a may be a parent relay node or a DU associated with a donor node. That is, parent
node 710-a may generally refer to a first node, in communication with relay node 705,
under the control of the network management function (e.g., management control function),
or CU 310-b.
[0125] At 710, relay node 705 may (e.g., autonomously) establish a second backhaul link
between the second MT function (e.g., MT 715-d) and a second parent node (e.g., parent
node 710-b). In some cases, the second backhaul link may be established based on the
relay node 705 measuring, using the MT 715-d, one or more parent nodes, and selecting
parent node 710-b based on a parent-selection policy (e.g., which may be the same
parent-selection policy or a different parent-selection policy used by MT 715-a).
The second backhaul link may connect relay node 705 (e.g., specifically MT 715-d)
to a network management function (e.g., CU 310-b) through parent node 710-b. As discussed
above, in some cases parent node 710-b may be a parent relay node, or a DU associated
with a donor node. That is, parent node 710-b may generally refer to a second node,
in communication with relay node 705, under the control of the management control
function, or CU 310-b.
[0126] At 715, the relay node 705 exchanges an identifier of the relay node, using MT 715-a,
with the network management function. In some cases, the network management function
may generate a relay identifier for the relay node 705 (e.g., during link establishment
at 705) and may transmit the relay identifier to the MT 715-a. In other cases, relay
node 705 may identify a relay identifier (e.g., based on a node identification number)
and transmit the relay identifier to the network management function (e.g., via the
first backhaul link to parent node 710-a).
[0127] At 720, relay node 705 then, using MT 715-d, transmit the same relay identifier (e.g.,
identified or received at 715) to the network management function via the second backhaul
link to parent node 710-b.
[0128] At 725, the network management function receives the relay identifier over the two
links (e.g., from parent node 710-a and parent node 710-b) and may identify the relay
node 705 is dual-connected to the network management function (e.g., the network management
function may identify the two relay identifiers received over the two links are associated
with the same relay node 705 and may deduce that relay node 705 is dual-connected
to the network management function.
[0129] At 730, the network management function may coordinate use of the first and second
backhaul links based on the identification that the relay node 705 is dual-connected
to the network management function. For example, the network management function may
identify a backhaul link configuration for the second connected MT (e.g., MT 715-d).
[0130] At 735, the network management function transmits a backhaul link configuration to
the MT 715-d over the second link, or may transmit a backhaul link configuration for
the MT 715-d over the first link to MT 715-a, where the backhaul link configuration
includes an identifier of the MT 715-d (e.g., such that MT 715-a knows the backhaul
link configuration applies to MT 715-d, and forwards the backhaul link configuration
to MT 715-d). In some cases, the first backhaul link may be additionally or alternatively
configured at 730 and 735. In general, the network management function may coordinate
configuration of the first and second backhaul links upon determination that the relay
node 705 is dual-connected to the network management function.
[0131] FIG. 8 shows a block diagram 800 of a device 805 that supports relay nodes with multi-connected
cellular backhaul in accordance with one or more aspects of the present disclosure.
The device 805 may be an example of aspects of a relay node (e.g., such as a relay
network device 105 or a relay base station 105, a relay IAB node 320, relay node 505,
relay node 705) as described herein. The device 805 may include a receiver 810, a
communications manager 815, and a transmitter 820. The device 805 may also include
a processor. Each of these components may be in communication with one another (e.g.,
via one or more buses).
[0132] The receiver 810 may receive information such as packets, user data, or control information
associated with various information channels (e.g., control channels, data channels,
and information related to relay nodes with multi-connected cellular backhaul, etc.).
Information may be passed on to other components of the device 805. The receiver 810
may be an example of aspects of the transceiver 1120 described with reference to FIG.
11. The receiver 810 may utilize a single antenna or a set of antennas.
[0133] The communications manager 815 may transmit, using a first mobile terminal function
of the relay node, a measurement report to a network management function via a first
backhaul link to a first parent node, where the measurement report includes measurements
of a second parent node transmission. The communications manager 815 may receive,
via the first backhaul link using the first mobile terminal function of the relay
node, a backhaul link configuration for the second mobile terminal function based
on the transmitted measurement report. The communications manager 815 may establish
a second backhaul link between the second mobile terminal function of the relay node
and the second parent node based on the received backhaul link configuration.
[0134] The communications manager 815 may also exchange, using a first mobile terminal function
of the relay node, an identifier of the relay node with a first network management
function via a first backhaul link to a first parent node. The communications manager
815 may transmit, using a second mobile terminal function of the relay node, the identifier
of the relay node to a second network management function via a second backhaul link
to a second parent node. The communications manager 815 may receive a backhaul link
configuration for the second mobile terminal function based on the transmission of
the identifier of the relay node to the first network management function via the
first backhaul link and the transmission of the identifier of the relay node to the
second network management function via the second backhaul link. The communications
manager 815 may be an example of aspects of the communications manager 1110 described
herein.
[0135] The communications manager 815, or its sub-components, may be implemented in hardware,
code (e.g., software or firmware) executed by a processor, or any combination thereof.
If implemented in code executed by a processor, the functions of the communications
manager 815, or its sub-components may be executed by a general-purpose processor,
a digital signal processor (DSP), an application-specific integrated circuit (ASIC),
a field-programmable gate array (FPGA) or other programmable logic device, discrete
gate or transistor logic, discrete hardware components, or any combination thereof
designed to perform the functions described in the present disclosure.
[0136] The communications manager 815, or its sub-components, may be physically located
at various positions, including being distributed such that portions of functions
are implemented at different physical locations by one or more physical components.
In some examples, the communications manager 815, or its sub-components, may be a
separate and distinct component in accordance with various aspects of the present
disclosure. In some examples, the communications manager 815, or its sub-components,
may be combined with one or more other hardware components, including but not limited
to an input/output (I/O) component, a transceiver, a network server, another computing
device, one or more other components described in the present disclosure, or a combination
thereof in accordance with various aspects of the present disclosure.
[0137] The transmitter 820 may transmit signals generated by other components of the device
805. In some examples, the transmitter 820 may be collocated with a receiver 810 in
a transceiver module. For example, the transmitter 820 may be an example of aspects
of the transceiver 1120 described with reference to FIG. 11. The transmitter 820 may
utilize a single antenna or a set of antennas.
[0138] FIG. 9 shows a block diagram 900 of a device 905 that supports relay nodes with multi-connected
cellular backhaul in accordance with one or more aspects of the present disclosure.
The device 905 may be an example of aspects of a device 805, or a relay node (e.g.,
such as a relay network device 105 or a relay base station 105, a relay IAB node 320,
relay node 505, relay node 705) as described herein. The device 905 may include a
receiver 910, a communications manager 915, and a transmitter 940. The device 905
may also include a processor. Each of these components may be in communication with
one another (e.g., via one or more buses).
[0139] The receiver 910 may receive information such as packets, user data, or control information
associated with various information channels (e.g., control channels, data channels,
and information related to relay nodes with multi-connected cellular backhaul, etc.).
Information may be passed on to other components of the device 905. The receiver 910
may be an example of aspects of the transceiver 1120 described with reference to FIG.
11. The receiver 910 may utilize a single antenna or a set of antennas.
[0140] The communications manager 915 may be an example of aspects of the communications
manager 815 as described herein. The communications manager 915 may include a measurement
report manager 920, a backhaul link configuration manager 925, a backhaul link manager
930, and a relay node ID manager 935. The communications manager 915 may be an example
of aspects of the communications manager 1110 described herein.
[0141] The measurement report manager 920 may transmit, using a first mobile terminal function
of the relay node, a measurement report to a network management function via a first
backhaul link to a first parent node, where the measurement report includes measurements
of a second parent node transmission.
[0142] The backhaul link configuration manager 925 may receive, via the first backhaul link
using the first mobile terminal function of the relay node, a backhaul link configuration
for the second mobile terminal function based on the transmitted measurement report.
[0143] The backhaul link manager 930 may establish a second backhaul link between the second
mobile terminal function of the relay node and the second parent node based on the
received backhaul link configuration.
[0144] The relay node ID manager 935 may exchange, using a first mobile terminal function
of the relay node, an identifier of the relay node with a first network management
function via a first backhaul link to a first parent node and transmit, using a second
mobile terminal function of the relay node, the identifier of the relay node to a
second network management function via a second backhaul link to a second parent node.
[0145] The backhaul link configuration manager 925 may receive a backhaul link configuration
for the second mobile terminal function based on the transmission of the identifier
of the relay node to the first network management function via the first backhaul
link and the transmission of the identifier of the relay node to the second network
management function via the second backhaul link.
[0146] The transmitter 940 may transmit signals generated by other components of the device
905. In some examples, the transmitter 940 may be collocated with a receiver 910 in
a transceiver module. For example, the transmitter 940 may be an example of aspects
of the transceiver 1120 described with reference to FIG. 11. The transmitter 940 may
utilize a single antenna or a set of antennas.
[0147] FIG. 10 shows a block diagram 1000 of a communications manager 1005 that supports relay nodes
with multi-connected cellular backhaul in accordance with one or more aspects of the
present disclosure. The communications manager 1005 may be an example of aspects of
a communications manager 815, a communications manager 915, or a communications manager
1110 described herein. The communications manager 1005 may include a measurement report
manager 1010, a backhaul link configuration manager 1015, a backhaul link manager
1020, a MT capability manager 1025, a measurement configuration manager 1030, a parent
node measurement manager 1035, a relay node ID manager 1040, and a management function
ID manager 1045. Each of these modules may communicate, directly or indirectly, with
one another (e.g., via one or more buses).
[0148] The measurement report manager 1010 may transmit, using a first mobile terminal function
of the relay node, a measurement report to a network management function via a first
backhaul link to a first parent node, where the measurement report includes measurements
of a second parent node transmission.
[0149] The backhaul link configuration manager 1015 may receive, via the first backhaul
link using the first mobile terminal function of the relay node, a backhaul link configuration
for the second mobile terminal function based on the transmitted measurement report.
In some examples, the backhaul link configuration manager 1015 may receive a backhaul
link configuration for the second mobile terminal function based on the transmission
of the identifier of the relay node to the first network management function via the
first backhaul link and the transmission of the identifier of the relay node to the
second network management function via the second backhaul link.
[0150] In some examples, receiving a routing configuration for the first backhaul link and
the second backhaul link, where the routing configuration includes route utilization
information, link utilization information, resource allocation information, or some
combination thereof. In some cases, the backhaul link configuration for the second
mobile terminal function includes an identifier of the second mobile terminal function
of the relay node, an identifier of the second parent node, route configuration parameters,
or some combination thereof. In some cases, the backhaul link configuration for the
second mobile terminal function is received in a container of a RRC message received
by the first mobile terminal function. In some cases, the backhaul link configuration
for the second mobile terminal function is received in F1-AP signaling. In some cases,
the first network management function and the second network management function each
include a gNB, a gNB-CU, a gNB-CU-CP, an eNB, an eNB-CU, an eNB-CU-CP, a centralized
controller, a topology function, a route function, a resource function, or some combination
thereof.
[0151] The backhaul link manager 1020 may establish a second backhaul link between the second
mobile terminal function of the relay node and the second parent node based on the
received backhaul link configuration. In some examples, the backhaul link manager
1020 may exchange backhaul information with the fist network management function via
the first backhaul link to the first parent node using the first mobile terminal function,
with the second network management function via the second backhaul link to the second
parent node using the second mobile terminal function, or both, based on the received
backhaul link configuration.
[0152] In some examples, the backhaul link manager 1020 may establish the first backhaul
link between the first mobile terminal function of the relay node and the first parent
node, where the identifier of the relay node is transmitted to the first network management
function via the established first backhaul link. In some examples, the backhaul link
manager 1020 may establish the second backhaul link between the second mobile terminal
function of the relay node and the second parent node, where the identifier of the
relay node is transmitted to the second network management function via the established
second backhaul link. In some examples, the backhaul link manager 1020 may exchange
backhaul information using the first backhaul link, the second backhaul link, or both,
based on the received backhaul link configuration.
[0153] In some cases, the first parent node and the second parent node are associated with
the network management function supported by a CU. In some cases, the network management
function includes a gNB, a gNB-CU, a gNB-CU-CP, an eNB, an eNB-CU, an eNB-CU-CP, a
centralized controller, a topology function, a route function, a resource function,
or some combination thereof.
[0154] The relay node ID manager 1040 may exchange, using a first mobile terminal function
of the relay node, an identifier of the relay node with a first network management
function via a first backhaul link to a first parent node. In some examples, the relay
node ID manager 1040 may transmit, using a second mobile terminal function of the
relay node, the identifier of the relay node to a second network management function
via a second backhaul link to a second parent node.
[0155] The MT capability manager 1025 may transmit, via the first backhaul link using the
first mobile terminal function, a capability report to the network management function.
In some examples, the MT capability manager 1025 may transmit, using the second mobile
terminal function, a capability report to the second parent node, where the capability
report includes an identifier of the second mobile terminal function, one or more
RATs supported by the second mobile terminal function, one or more frequency bands
supported by the second mobile terminal function, azimuth and elevation patterns supported
by the second mobile terminal function, RF capabilities of the second mobile terminal
function, isolation between the first mobile terminal function and the second mobile
terminal function, an identifier of the relay node, a list of supported mobile terminal
functions, or some combination thereof.
[0156] In some cases, the capability report includes an identifier of the second mobile
terminal function, one or more RATs supported by the second mobile terminal function,
one or more frequency bands supported by the second mobile terminal function, azimuth
and elevation patterns supported by the second mobile terminal function, RF capabilities
of the second mobile terminal function, isolation between the first and second mobile
terminal function, an identifier of the relay node, a list of supported mobile terminal
functions, or some combination thereof.
[0157] The measurement configuration manager 1030 may receive, via the first backhaul link
using the first mobile terminal function of the relay node, a measurement configuration
for the second mobile terminal function of the relay node based on the transmitted
capability report. In some examples, the measurement configuration manager 1030 may
receive, using the first mobile terminal function of the relay node, a measurement
configuration for the second mobile terminal function, where the one or more signal
strength measurements are performed based on the received measurement configuration.
In some cases, the measurement configuration includes an identifier of the second
mobile terminal function, an identifier of the second parent node, or some combination
thereof.
[0158] The parent node measurement manager 1035 may perform, using the second mobile terminal
function of the relay node, measurements of the second parent node transmission based
on the measurement configuration, where the transmitted measurement report includes
the measurements. In some examples, the parent node measurement manager 1035 may perform,
using the second mobile terminal function, one or more signal strength measurements
of one or more parent nodes. In some examples, the parent node measurement manager
1035 may identify the second parent node based on the one or more signal strength
measurements, where the second backhaul link is established based on the identified
second parent node.
[0159] The management function ID manager 1045 may receive an identifier of the first network
management function associated with the first backhaul link. In some examples, the
management function ID manager 1045 may receive an identifier of the second network
management function associated with the second backhaul link. In some examples, the
management function ID manager 1045 may determine the identifier of the first management
function associated with the first backhaul link is different from the identifier
of the second management function associated with the second backhaul link. In some
examples, the management function ID manager 1045 may identify the backhaul link configuration
for the second mobile terminal function is associated with the second management function
of the second backhaul link. In some examples, the management function ID manager
1045 may determine the identifier of the first management function associated with
the first backhaul link is the same as the identifier of the second management function
associated with the second backhaul link. In some examples, the management function
ID manager 1045 may identify the backhaul link configuration for the second mobile
terminal function is associated with a same management function of the first backhaul
link and second backhaul link.
[0160] FIG. 11 shows a diagram of a system 1100 including a device 1105 that supports relay nodes
with multi-connected cellular backhaul in accordance with one or more aspects of the
present disclosure. The device 1105 may be an example of or include the components
of device 805, device 905, or a relay node (e.g., such as a relay base station 105,
a relay IAB node 320, relay node 505, relay node 705) as described herein. The device
1105 may include components for bi-directional voice and data communications including
components for transmitting and receiving communications, including a communications
manager 1110, an I/O controller 1115, a transceiver 1120, an antenna 1125, memory
1130, and a processor 1140. These components may be in electronic communication via
one or more buses (e.g., bus 1145).
[0161] The communications manager 1110 may transmit, using a first mobile terminal function
of the relay node, a measurement report to a network management function via a first
backhaul link to a first parent node, where the measurement report includes measurements
of a second parent node transmission, receive, via the first backhaul link using the
first mobile terminal function of the relay node, a backhaul link configuration for
the second mobile terminal function based on the transmitted measurement report, and
establish a second backhaul link between the second mobile terminal function of the
relay node and the second parent node based on the received backhaul link configuration.
The communications manager 1110 may also exchange, using a first mobile terminal function
of the relay node, an identifier of the relay node with a first network management
function via a first backhaul link to a first parent node, transmit, using a second
mobile terminal function of the relay node, the identifier of the relay node to a
second network management function via a second backhaul link to a second parent node,
and receive a backhaul link configuration for the second mobile terminal function
based on the transmission of the identifier of the relay node to the first network
management function via the first backhaul link and the transmission of the identifier
of the relay node to the second network management function via the second backhaul
link.
[0162] The I/O controller 1115 may manage input and output signals for the device 1105.
The I/O controller 1115 may also manage peripherals not integrated into the device
1105. In some cases, the I/O controller 1115 may represent a physical connection or
port to an external peripheral. In some cases, the I/O controller 1115 may utilize
an operating system such as iOS
®, ANDROID
®, MS-DOS
®, MS-WINDOWS
®, OS/29, UNIX
®, LINUX
®, or another known operating system. In other cases, the I/O controller 1115 may represent
or interact with a modem, a keyboard, a mouse, a touchscreen, or a similar device.
In some cases, the I/O controller 1115 may be implemented as part of a processor.
In some cases, a user may interact with the device 1105 via the I/O controller 1115
or via hardware components controlled by the I/O controller 1115.
[0163] The transceiver 1120 may communicate bi-directionally, via one or more antennas,
wired, or wireless links as described above. For example, the transceiver 1120 may
represent a wireless transceiver and may communicate bi-directionally with another
wireless transceiver. The transceiver 1120 may also include a modem to modulate the
packets and provide the modulated packets to the antennas for transmission, and to
demodulate packets received from the antennas.
[0164] In some cases, the wireless device may include a single antenna 1125. However, in
some cases the device may have more than one antenna 1125, which may be capable of
concurrently transmitting or receiving multiple wireless transmissions.
[0165] The memory 1130 may include RAM and ROM. The memory 1130 may store computer-readable,
computer-executable code or software 1135 including instructions that, when executed,
cause the processor to perform various functions described herein. In some cases,
the memory 1130 may contain, among other things, a BIOS which may control basic hardware
or software operation such as the interaction with peripheral components or devices.
[0166] The processor 1140 may include an intelligent hardware device, (e.g., a general-purpose
processor, a DSP, a CPU, a microcontroller, an ASIC, an FPGA, a programmable logic
device, a discrete gate or transistor logic component, a discrete hardware component,
or any combination thereof). In some cases, the processor 1140 may be configured to
operate a memory array using a memory controller. In other cases, a memory controller
may be integrated into the processor 1140. The processor 1140 may be configured to
execute computer-readable instructions stored in a memory (e.g., the memory 1130)
to cause the device 1105 to perform various functions (e.g., functions or tasks supporting
relay nodes with multi-connected cellular backhaul).
[0167] The software 1135 may include instructions to implement aspects of the present disclosure,
including instructions to support wireless communications. The software 1135 may be
stored in a non-transitory computer-readable medium such as system memory or other
type of memory. In some cases, the software 1135 may not be directly executable by
the processor 1140 but may cause a computer (e.g., when compiled and executed) to
perform functions described herein.
[0168] FIG. 12 shows a block diagram 1200 of a device 1205 that supports relay nodes with multi-connected
cellular backhaul in accordance with one or more aspects of the present disclosure.
The device 1205 may be an example of aspects of a base station 105, a parent node,
or a network management function as described herein. The device 1205 may include
a receiver 1210, a communications manager 1215, and a transmitter 1220. The device
1205 may also include a processor. Each of these components may be in communication
with one another (e.g., via one or more buses).
[0169] The receiver 1210 may receive information such as packets, user data, or control
information associated with various information channels (e.g., control channels,
data channels, and information related to relay nodes with multi-connected cellular
backhaul, etc.). Information may be passed on to other components of the device 1205.
The receiver 1210 may be an example of aspects of the transceiver 1520 described with
reference to FIG. 15. The receiver 1210 may utilize a single antenna or a set of antennas.
[0170] The communications manager 1215 may receive, by a network management function via
a first backhaul link, a measurement report from a first mobile terminal function
of a relay node, where the measurement report includes measurements of a second parent
node transmission. The communications manager 1215 may identify a backhaul link configuration
for the second mobile terminal function based on the received measurement report.
The communications manager 1215 may transmit, via the first backhaul link, the identified
backhaul link configuration for the second mobile terminal function to the first mobile
terminal function of the relay node.
[0171] The communications manager 1215 may also identify a relay node is connected to a
first parent node via a first mobile terminal function of the relay node, identify
the relay node is connected to a second parent node via a second mobile terminal function
of the relay node, and transmit a backhaul link configuration for the second mobile
terminal function based on the identified relay node connections. The communications
manager 1215 may be an example of aspects of the communications manager 1510 described
herein.
[0172] The communications manager 1215, or its sub-components, may be implemented in hardware,
code (e.g., software or firmware) executed by a processor, or any combination thereof.
If implemented in code executed by a processor, the functions of the communications
manager 1215, or its sub-components may be executed by a general-purpose processor,
a DSP, an ASIC, a FPGA or other programmable logic device, discrete gate or transistor
logic, discrete hardware components, or any combination thereof designed to perform
the functions described in the present disclosure.
[0173] The communications manager 1215, or its sub-components, may be physically located
at various positions, including being distributed such that portions of functions
are implemented at different physical locations by one or more physical components.
In some examples, the communications manager 1215, or its sub-components, may be a
separate and distinct component in accordance with various aspects of the present
disclosure. In some examples, the communications manager 1215, or its sub-components,
may be combined with one or more other hardware components, including but not limited
to an I/O component, a transceiver, a network server, another computing device, one
or more other components described in the present disclosure, or a combination thereof
in accordance with various aspects of the present disclosure.
[0174] The transmitter 1220 may transmit signals generated by other components of the device
1205. In some examples, the transmitter 1220 may be collocated with a receiver 1210
in a transceiver module. For example, the transmitter 1220 may be an example of aspects
of the transceiver 1520 described with reference to FIG. 15. The transmitter 1220
may utilize a single antenna or a set of antennas.
[0175] FIG. 13 shows a block diagram 1300 of a device 1305 that supports relay nodes with multi-connected
cellular backhaul in accordance with one or more aspects of the present disclosure.
The device 1305 may be an example of aspects of a device 1205, or aspects of a base
station 105, a parent node, or a network management function as described herein.
The device 1305 may include a receiver 1310, a communications manager 1315, and a
transmitter 1335. The device 1305 may also include a processor. Each of these components
may be in communication with one another (e.g., via one or more buses).
[0176] The receiver 1310 may receive information such as packets, user data, or control
information associated with various information channels (e.g., control channels,
data channels, and information related to relay nodes with multi-connected cellular
backhaul, etc.). Information may be passed on to other components of the device 1305.
The receiver 1310 may be an example of aspects of the transceiver 1520 described with
reference to FIG. 15. The receiver 1310 may utilize a single antenna or a set of antennas.
[0177] The communications manager 1315 may be an example of aspects of the communications
manager 1215 as described herein. The communications manager 1315 may include a measurement
report manager 1320, a backhaul link configuration manager 1325, and a backhaul link
manager 1330. The communications manager 1315 may be an example of aspects of the
communications manager 1510 described herein.
[0178] The measurement report manager 1320 may receive, by a network management function
via a first backhaul link, a measurement report from a first mobile terminal function
of a relay node, where the measurement report includes measurements of a second parent
node transmission.
[0179] The backhaul link configuration manager 1325 may identify a backhaul link configuration
for the second mobile terminal function based on the received measurement report and
transmit, via the first backhaul link, the identified backhaul link configuration
for the second mobile terminal function to the first mobile terminal function of the
relay node.
[0180] The backhaul link manager 1330 may identify a relay node is connected to a first
parent node via a first mobile terminal function of the relay node and identify the
relay node is connected to a second parent node via a second mobile terminal function
of the relay node.
[0181] The backhaul link configuration manager 1325 may transmit a backhaul link configuration
for the second mobile terminal function based on the identified relay node connections.
[0182] The transmitter 1335 may transmit signals generated by other components of the device
1305. In some examples, the transmitter 1335 may be collocated with a receiver 1310
in a transceiver module. For example, the transmitter 1335 may be an example of aspects
of the transceiver 1520 described with reference to FIG. 15. The transmitter 1335
may utilize a single antenna or a set of antennas.
[0183] FIG. 14 shows a block diagram 1400 of a communications manager 1405 that supports relay nodes
with multi-connected cellular backhaul in accordance with one or more aspects of the
present disclosure. The communications manager 1405 may be an example of aspects of
a communications manager 1215, a communications manager 1315, or a communications
manager 1510 described herein. The communications manager 1405 may include a measurement
report manager 1410, a backhaul link configuration manager 1415, a MT capability manager
1420, a measurement configuration manager 1425, a backhaul link manager 1430, a management
function ID manager 1435, and a relay node ID manager 1440. Each of these modules
may communicate, directly or indirectly, with one another (e.g., via one or more buses).
[0184] The measurement report manager 1410 may receive, by a network management function
via a first backhaul link, a measurement report from a first mobile terminal function
of a relay node, where the measurement report includes measurements of a second parent
node transmission.
[0185] The backhaul link configuration manager 1415 may identify a backhaul link configuration
for the second mobile terminal function based on the received measurement report.
In some examples, the backhaul link configuration manager 1415 may transmit, via the
first backhaul link, the identified backhaul link configuration for the second mobile
terminal function to the first mobile terminal function of the relay node. In some
examples, the backhaul link configuration manager 1415 may transmit a backhaul link
configuration for the second mobile terminal function based on the identified relay
node connections.
[0186] In some examples, transmitting a routing configuration for a second backhaul link,
between the second mobile terminal function of the relay node and the first parent
node, and a first backhaul link, between the first MT of the relay node and the first
parent node, where the routing configuration includes route utilization information,
link utilization information, resource allocation information, or some combination
thereof.
[0187] In some cases, the backhaul link configuration for the second mobile terminal function
includes an identifier of the second mobile terminal function of the relay node, an
identifier of the second parent node, route configuration parameters, or some combination
thereof. In some cases, the backhaul link configuration for the second mobile terminal
function is transmitted in a container of a RRC message to the first mobile terminal
function. In some cases, the backhaul link configuration for the second mobile terminal
function is transmitted in F1-AP signaling.
[0188] The backhaul link manager 1430 may identify a relay node is connected to a first
parent node via a first mobile terminal function of the relay node. In some examples,
the backhaul link manager 1430 may identify the relay node is connected to a second
parent node via a second mobile terminal function of the relay node. In some examples,
the backhaul link manager 1430 may receive backhaul information from the first mobile
terminal function of the relay node via the first parent node, from the second mobile
terminal function of the relay node via the second parent node, or both, based on
the transmitted backhaul link configuration. In some cases, the first backhaul link,
between the first mobile terminal function of the relay node and the first parent
node, and a second backhaul link, between the second mobile terminal function of the
relay node and the first parent node, are associated with a cellular RAT.
[0189] The MT capability manager 1420 may receive, via the first backhaul link, a capability
report from the first mobile terminal function of the relay node, where the capability
report includes capability information for the second mobile terminal function of
the relay node. In some cases, the capability report includes an identifier of the
second mobile terminal function, one or more RATs supported by the second mobile terminal
function, one or more frequency bands supported by the second mobile terminal function,
azimuth and elevation patterns supported by the second mobile terminal function, RF
capabilities of the second mobile terminal function, isolation between the first mobile
terminal function and the second mobile terminal function, an identifier of the relay
node, a list of supported mobile terminal functions, or some combination thereof.
[0190] The measurement configuration manager 1425 may identify a measurement configuration
for the second mobile terminal function of the relay node based on the received capability
report. In some examples, the measurement configuration manager 1425 may transmit,
via the first backhaul link, the identified measurement configuration to the first
mobile terminal function, where the measurement report is received based on the transmitted
measurement configuration. In some examples, transmitting a measurement configuration
for the second mobile terminal function to the relay node, where the measurement configuration
includes an identifier of the second parent node, policy information for relay node
selection of the second parent node, or some combination thereof. In some cases, the
measurement configuration includes an identifier of the second mobile terminal function,
an identifier of the second parent node, or some combination thereof.
[0191] The management function ID manager 1435 may transmit a network management function
identifier to the relay node via the first parent node. In some examples, the management
function ID manager 1435 may transmit the management function identifier to the relay
node via the second parent node. The relay node ID manager 1440 may receive an identifier
of the relay node from the first parent node. In some examples, the relay node ID
manager 1440 may receive the identifier of the relay node from the second parent node,
where the identification that the relay node is connected to the second parent node
via the second mobile terminal function of the relay node is based on the identifier
of the relay node from the second parent node being the same as the identifier of
the relay node from the first parent node.
[0192] FIG. 15 shows a diagram of a system 1500 including a device 1505 that supports relay nodes
with multi-connected cellular backhaul in accordance with one or more aspects of the
present disclosure. The device 1505 may be an example of or include the components
of device 1205, device 1305, or aspects of a base station 105, a parent node, or a
network management function as described herein. The device 1505 may include components
for bi-directional voice and data communications including components for transmitting
and receiving communications, including a communications manager 1510, a network communications
manager 1515, a transceiver 1520, an antenna 1525, memory 1530, a processor 1540,
and an inter-station communications manager 1545. These components may be in electronic
communication via one or more buses (e.g., bus 1550).
[0193] The communications manager 1510 may receive, by a network management function via
a first backhaul link, a measurement report from a first mobile terminal function
of a relay node, where the measurement report includes measurements of a second parent
node transmission, identify a backhaul link configuration for the second mobile terminal
function based on the received measurement report, and transmit, via the first backhaul
link, the identified backhaul link configuration for the second mobile terminal function
to the first mobile terminal function of the relay node. The communications manager
1510 may also identify a relay node is connected to a first parent node via a first
mobile terminal function of the relay node, identify the relay node is connected to
a second parent node via a second mobile terminal function of the relay node, and
transmit a backhaul link configuration for the second mobile terminal function based
on the identified relay node connections.
[0194] The network communications manager 1515 may manage communications with the core network
(e.g., via one or more wired backhaul links). For example, the network communications
manager 1515 may manage the transfer of data communications for client devices, such
as one or more UEs 115.
[0195] The transceiver 1520 may communicate bi-directionally, via one or more antennas,
wired, or wireless links as described above. For example, the transceiver 1520 may
represent a wireless transceiver and may communicate bi-directionally with another
wireless transceiver. The transceiver 1520 may also include a modem to modulate the
packets and provide the modulated packets to the antennas for transmission, and to
demodulate packets received from the antennas.
[0196] In some cases, the wireless device may include a single antenna 1525. However, in
some cases the device may have more than one antenna 1525, which may be capable of
concurrently transmitting or receiving multiple wireless transmissions.
[0197] The memory 1530 may include RAM, ROM, or a combination thereof. The memory 1530 may
store computer-readable code or software 1535 including instructions that, when executed
by a processor (e.g., the processor 1540) cause the device to perform various functions
described herein. In some cases, the memory 1530 may contain, among other things,
a BIOS which may control basic hardware or software operation such as the interaction
with peripheral components or devices.
[0198] The processor 1540 may include an intelligent hardware device, (e.g., a general-purpose
processor, a DSP, a CPU, a microcontroller, an ASIC, an FPGA, a programmable logic
device, a discrete gate or transistor logic component, a discrete hardware component,
or any combination thereof). In some cases, the processor 1540 may be configured to
operate a memory array using a memory controller. In some cases, a memory controller
may be integrated into processor 1540. The processor 1540 may be configured to execute
computer-readable instructions stored in a memory (e.g., the memory 1530) to cause
the device 1505 to perform various functions (e.g., functions or tasks supporting
relay nodes with multi-connected cellular backhaul).
[0199] The inter-station communications manager 1545 may manage communications with other
base station 105, and may include a controller or scheduler for controlling communications
with UEs 115 in cooperation with other base stations 105. For example, the inter-station
communications manager 1545 may coordinate scheduling for transmissions to UEs 115
for various interference mitigation techniques such as beamforming or joint transmission.
In some examples, the inter-station communications manager 1545 may provide an X2
interface within an LTE/LTE-A wireless communication network technology to provide
communication between base stations 105.
[0200] The software 1535 may include instructions to implement aspects of the present disclosure,
including instructions to support wireless communications. The software 1535 may be
stored in a non-transitory computer-readable medium such as system memory or other
type of memory. In some cases, the software 1535 may not be directly executable by
the processor 1540 but may cause a computer (e.g., when compiled and executed) to
perform functions described herein.
[0201] FIG. 16 shows a flowchart illustrating a method 1600 that supports relay nodes with multi-connected
cellular backhaul in accordance with one or more aspects of the present disclosure.
The operations of method 1600 may be implemented by a relay node or its components
as described herein. For example, the operations of method 1600 may be performed by
a communications manager as described with reference to FIGs. 8 through 11. In some
examples, a relay node may execute a set of instructions to control the functional
elements of the relay node to perform the functions described below. Additionally
or alternatively, a relay node may perform aspects of the functions described below
using special-purpose hardware.
[0202] At 1605, the relay node may transmit, using a first mobile terminal function of the
relay node, a measurement report to a network management function via a first backhaul
link to a first parent node, where the measurement report includes measurements of
a second parent node trans. The operations of 1605 may be performed according to the
methods described herein. In some examples, aspects of the operations of 1605 may
be performed by a measurement report manager as described with reference to FIGs.
8 through 11.
[0203] At 1610, the relay node may establish a second backhaul link between the second mobile
terminal function of the relay node and the second parent node based on the received
backhaul link configuration. The operations of 1610 may be performed according to
the methods described herein. In some examples, aspects of the operations of 1610
may be performed by a backhaul link manager as described with reference to FIGs. 8
through 11.
[0204] At 1615, the relay node may receive, via the first backhaul link using the first
mobile terminal function of the relay node, a backhaul link configuration for the
second mobile terminal function based on the transmitted measurement report. The operations
of 1615 may be performed according to the methods described herein. In some examples,
aspects of the operations of 1615 may be performed by a backhaul link configuration
manager as described with reference to FIGs. 8 through 11.
[0205] FIG. 17 shows a flowchart illustrating a method 1700 that supports relay nodes with multi-connected
cellular backhaul in accordance with one or more aspects of the present disclosure.
The operations of method 1700 may be implemented by a relay node or its components
as described herein. For example, the operations of method 1700 may be performed by
a communications manager as described with reference to FIGs. 8 through 11. In some
examples, a relay node may execute a set of instructions to control the functional
elements of the relay node to perform the functions described below. Additionally
or alternatively, a relay node may perform aspects of the functions described below
using special-purpose hardware.
[0206] At 1705, the relay node may transmit, via the first backhaul link using the first
mobile terminal function, a capability report to the network management function.
The operations of 1705 may be performed according to the methods described herein.
In some examples, aspects of the operations of 1705 may be performed by a MT capability
manager as described with reference to FIGs. 8 through 11.
[0207] At 1710, the relay node may receive, via the first backhaul link using the first
mobile terminal function of the relay node, a measurement configuration for the second
mobile terminal function of the relay node based on the transmitted capability report.
The operations of 1710 may be performed according to the methods described herein.
In some examples, aspects of the operations of 1710 may be performed by a measurement
configuration manager as described with reference to FIGs. 8 through 11.
[0208] At 1715, the relay node may perform, using the second mobile terminal function of
the relay node, measurements of the second parent node transmission based on the measurement
configuration, where the transmitted measurement report includes the measurements.
The operations of 1715 may be performed according to the methods described herein.
In some examples, aspects of the operations of 1715 may be performed by a parent node
measurement manager as described with reference to FIGs. 8 through 11.
[0209] At 1720, the relay node may transmit, using a first mobile terminal function of the
relay node, a measurement report to a network management function via a first backhaul
link to a first parent node, where the measurement report includes measurements of
a second parent node transmission. The operations of 1720 may be performed according
to the methods described herein. In some examples, aspects of the operations of 1720
may be performed by a measurement report manager as described with reference to FIGs.
8 through 11.
[0210] At 1725, the relay node may establish a second backhaul link between the second mobile
terminal function of the relay node and the second parent node based on the received
backhaul link configuration. The operations of 1725 may be performed according to
the methods described herein. In some examples, aspects of the operations of 1725
may be performed by a backhaul link manager as described with reference to FIGs. 8
through 11.
[0211] At 1730, the relay node may receive, via the first backhaul link using the first
mobile terminal function of the relay node, a backhaul link configuration for the
second mobile terminal function based on the transmitted measurement report. The operations
of 1730 may be performed according to the methods described herein. In some examples,
aspects of the operations of 1730 may be performed by a backhaul link configuration
manager as described with reference to FIGs. 8 through 11.
[0212] At 1735, the relay node may receive a routing configuration for the first backhaul
link and the second backhaul link, where the routing configuration includes route
utilization information, link utilization information, resource allocation information,
or some combination thereof. The operations of 1735 may be performed according to
the methods described herein. In some examples, aspects of the operations of 1735
may be performed by a backhaul link configuration manager as described with reference
to FIGs. 8 through 11.
[0213] FIG. 18 shows a flowchart illustrating a method 1800 that supports relay nodes with multi-connected
cellular backhaul in accordance with one or more aspects of the present disclosure.
The operations of method 1800 may be implemented by a management function (e.g., or
CU or base station) or its components as described herein. For example, the operations
of method 1800 may be performed by a communications manager as described with reference
to FIGs. 12 through 15. In some examples, a management function (e.g., or CU or base
station) may execute a set of instructions to control the functional elements of the
management function (e.g., or CU or base station) to perform the functions described
below. Additionally or alternatively, a management function (e.g., or CU or base station)
may perform aspects of the functions described below using special-purpose hardware.
[0214] At 1805, the management function (e.g., or CU or base station) may receive, by a
network management function via a first backhaul link, a measurement report from a
first mobile terminal function of a relay node, where the measurement report includes
measurements of a second parent node transmission. The operations of 1805 may be performed
according to the methods described herein. In some examples, aspects of the operations
of 1805 may be performed by a measurement report manager as described with reference
to FIGs. 12 through 15.
[0215] At 1810, the management function (e.g., or CU or base station) may identify a backhaul
link configuration for the second mobile terminal function based on the received measurement
report. The operations of 1810 may be performed according to the methods described
herein. In some examples, aspects of the operations of 1810 may be performed by a
backhaul link configuration manager as described with reference to FIGs. 12 through
15.
[0216] At 1815, the management function (e.g., or CU or base station) may transmit, via
the first backhaul link, the identified backhaul link configuration for the second
mobile terminal function to the first mobile terminal function of the relay node.
The operations of 1815 may be performed according to the methods described herein.
In some examples, aspects of the operations of 1815 may be performed by a backhaul
link configuration manager as described with reference to FIGs. 12 through 15.
[0217] FIG. 19 shows a flowchart illustrating a method 1900 that supports relay nodes with multi-connected
cellular backhaul in accordance with one or more aspects of the present disclosure.
The operations of method 1900 may be implemented by a relay node or its components
as described herein. For example, the operations of method 1900 may be performed by
a communications manager as described with reference to FIGs. 8 through 11. In some
examples, a relay node may execute a set of instructions to control the functional
elements of the relay node to perform the functions described below. Additionally
or alternatively, a relay node may perform aspects of the functions described below
using special-purpose hardware.
[0218] At 1905, the relay node may exchange, using a first mobile terminal function of the
relay node, an identifier of the relay node with a first network management function
via a first backhaul link to a first parent node. The operations of 1905 may be performed
according to the methods described herein. In some examples, aspects of the operations
of 1905 may be performed by a relay node ID manager as described with reference to
FIGs. 8 through 11.
[0219] At 1910, the relay node may transmit, using a second mobile terminal function of
the relay node, the identifier of the relay node to a second network management function
via a second backhaul link to a second parent node. The operations of 1910 may be
performed according to the methods described herein. In some examples, aspects of
the operations of 1910 may be performed by a relay node ID manager as described with
reference to FIGs. 8 through 11.
[0220] At 1915, the relay node may receive a backhaul link configuration for the second
mobile terminal function based on the transmission of the identifier of the relay
node to the first network management function via the first backhaul link and the
transmission of the identifier of the relay node to the second network management
function via the second backhaul link. The operations of 1915 may be performed according
to the methods described herein. In some examples, aspects of the operations of 1915
may be performed by a backhaul link configuration manager as described with reference
to FIGs. 8 through 11.
[0221] FIG. 20 shows a flowchart illustrating a method 2000 that supports relay nodes with multi-connected
cellular backhaul in accordance with one or more aspects of the present disclosure.
The operations of method 2000 may be implemented by a management function (e.g., or
CU or base station) or its components as described herein. For example, the operations
of method 2000 may be performed by a communications manager as described with reference
to FIGs. 12 through 15. In some examples, a management function (e.g., or CU or base
station) may execute a set of instructions to control the functional elements of the
management function (e.g., or CU or base station) to perform the functions described
below. Additionally or alternatively, a management function (e.g., or CU or base station)
may perform aspects of the functions described below using special-purpose hardware.
[0222] At 2005, the management function (e.g., or CU or base station) may identify a relay
node is connected to a first parent node via a first mobile terminal function of the
relay node. The operations of 2005 may be performed according to the methods described
herein. In some examples, aspects of the operations of 2005 may be performed by a
backhaul link manager as described with reference to FIGs. 12 through 15.
[0223] At 2010, the management function (e.g., or CU or base station) may identify the relay
node is connected to a second parent node via a second mobile terminal function of
the relay node. The operations of 2010 may be performed according to the methods described
herein. In some examples, aspects of the operations of 2010 may be performed by a
backhaul link manager as described with reference to FIGs. 12 through 15.
[0224] At 2015, the management function (e.g., or CU or base station) transmit a backhaul
link configuration for the second mobile terminal function based on the identified
relay node connections. The operations of 2015 may be performed according to the methods
described herein. In some examples, aspects of the operations of 2015 may be performed
by a backhaul link configuration manager as described with reference to FIGs. 12 through
15.
[0225] Techniques described herein may be used for various wireless communications systems
such as CDMA, TDMA, FDMA, OFDMA, single carrier frequency division multiple access
(SC-FDMA), and other systems. A CDMA system may implement a radio technology such
as CDMA2000, Universal Terrestrial Radio Access (UTRA), etc. CDMA2000 covers IS-2000,
IS-95, and IS-856 standards. IS-2000 Releases may be commonly referred to as CDMA2000
1X, 1X, etc. IS-856 (TIA-856) is commonly referred to as CDMA2000 1xEV-DO, High Rate
Packet Data (HRPD), etc. UTRA includes Wideband CDMA (WCDMA) and other variants of
CDMA. A TDMA system may implement a radio technology such as Global System for Mobile
Communications (GSM).
[0226] An OFDMA system may implement a radio technology such as Ultra Mobile Broadband (UMB),
Evolved UTRA (E-UTRA), Institute of Electrical and Electronics Engineers (IEEE) 802.11
(Wi-Fi), IEEE 802.16 (WiMAX), IEEE 802.20, Flash-OFDM, etc. UTRA and E-UTRA are part
of Universal Mobile Telecommunications System (UMTS). LTE, LTE-A, and LTE-A Pro are
releases of UMTS that use E-UTRA. UTRA, E-UTRA, UMTS, LTE, LTE-A, LTE-A Pro, NR, and
GSM are described in documents from the organization named "3rd Generation Partnership
Project" (3GPP). CDMA2000 and UMB are described in documents from an organization
named "3rd Generation Partnership Project 2" (3GPP2). The techniques described herein
may be used for the systems and radio technologies mentioned herein as well as other
systems and radio technologies. While aspects of an LTE, LTE-A, LTE-A Pro, or NR system
may be described for purposes of example, and LTE, LTE-A, LTE-A Pro, or NR terminology
may be used in much of the description, the techniques described herein are applicable
beyond LTE, LTE-A, LTE-A Pro, or NR applications.
[0227] A macro cell generally covers a relatively large geographic area (e.g., several kilometers
in radius) and may allow unrestricted access by UEs 115 with service subscriptions
with the network provider. A small cell may be associated with a lower-powered base
station 105, as compared with a macro cell, and a small cell may operate in the same
or different (e.g., licensed, unlicensed, etc.) frequency bands as macro cells. Small
cells may include pico cells, femto cells, and micro cells according to various examples.
A pico cell, for example, may cover a small geographic area and may allow unrestricted
access by UEs 115 with service subscriptions with the network provider. A femto cell
may also cover a small geographic area (e.g., a home) and may provide restricted access
by UEs 115 having an association with the femto cell (e.g., UEs 115 in a closed subscriber
group (CSG), UEs 115 for users in the home, and the like). An eNB for a macro cell
may be referred to as a macro eNB. An eNB for a small cell may be referred to as a
small cell eNB, a pico eNB, a femto eNB, or a home eNB. An eNB may support one or
multiple (e.g., two, three, four, and the like) cells, and may also support communications
using one or multiple component carriers.
[0228] The wireless communications system 100 or systems described herein may support synchronous
or asynchronous operation. For synchronous operation, the base stations 105 may have
similar frame timing, and transmissions from different base stations 105 may be approximately
aligned in time. For asynchronous operation, the base stations 105 may have different
frame timing, and transmissions from different base stations 105 may not be aligned
in time. The techniques described herein may be used for either synchronous or asynchronous
operations.
[0229] Information and signals described herein may be represented using any of a variety
of different technologies and techniques. For example, data, instructions, commands,
information, signals, bits, symbols, and chips that may be referenced throughout the
description may be represented by voltages, currents, electromagnetic waves, magnetic
fields or particles, optical fields or particles, or any combination thereof.
[0230] The various illustrative blocks and modules described in connection with the disclosure
herein may be implemented or performed with a general-purpose processor, a DSP, an
ASIC, a FPGA or other programmable logic device (PLD), discrete gate or transistor
logic, discrete hardware components, or any combination thereof designed to perform
the functions described herein. A general-purpose processor may be a microprocessor,
but in the alternative, the processor may be any conventional processor, controller,
microcontroller, or state machine. A processor may also be implemented as a combination
of computing devices (e.g., a combination of a DSP and a microprocessor, multiple
microprocessors, one or more microprocessors in conjunction with a DSP core, or any
other such configuration).
[0231] The functions described herein may be implemented in hardware, software executed
by a processor, firmware, or any combination thereof. If implemented in software executed
by a processor, the functions may be stored on or transmitted over as one or more
instructions or code on a computer-readable medium. Other examples and implementations
are within the scope of the disclosure and appended claims. For example, due to the
nature of software, functions described herein can be implemented using software executed
by a processor, hardware, firmware, hardwiring, or combinations of any of these. Features
implementing functions may also be physically located at various positions, including
being distributed such that portions of functions are implemented at different physical
locations.
[0232] Computer-readable media includes both non-transitory computer storage media and communication
media including any medium that facilitates transfer of a computer program from one
place to another. A non-transitory storage medium may be any available medium that
can be accessed by a general purpose or special purpose computer. By way of example,
and not limitation, non-transitory computer-readable media may include random-access
memory (RAM), read-only memory (ROM), electrically erasable programmable read only
memory (EEPROM), flash memory, compact disk (CD) ROM or other optical disk storage,
magnetic disk storage or other magnetic storage devices, or any other non-transitory
medium that can be used to carry or store desired program code means in the form of
instructions or data structures and that can be accessed by a general-purpose or special-purpose
computer, or a general-purpose or special-purpose processor. Also, any connection
is properly termed a computer-readable medium. For example, if the software is transmitted
from a website, server, or other remote source using a coaxial cable, fiber optic
cable, twisted pair, digital subscriber line (DSL), or wireless technologies such
as infrared, radio, and microwave, then the coaxial cable, fiber optic cable, twisted
pair, DSL, or wireless technologies such as infrared, radio, and microwave are included
in the definition of medium. Disk and disc, as used herein, include CD, laser disc,
optical disc, digital versatile disc (DVD), floppy disk and Blu-ray disc where disks
usually reproduce data magnetically, while discs reproduce data optically with lasers.
Combinations of the above are also included within the scope of computer-readable
media.
[0233] As used herein, including in the claims, "or" as used in a list of items (e.g., a
list of items prefaced by a phrase such as "at least one of" or "one or more of')
indicates an inclusive list such that, for example, a list of at least one of A, B,
or C means A or B or C or AB or AC or BC or ABC (i.e., A and B and C). Also, as used
herein, the phrase "based on" shall not be construed as a reference to a closed set
of conditions. For example, an exemplary step that is described as "based on condition
A" may be based on both a condition A and a condition B without departing from the
scope of the present disclosure. In other words, as used herein, the phrase "based
on" shall be construed in the same manner as the phrase "based at least in part on."
[0234] In the appended figures, similar components or features may have the same reference
label. Further, various components of the same type may be distinguished by following
the reference label by a dash and a second label that distinguishes among the similar
components. If just the first reference label is used in the specification, the description
is applicable to any one of the similar components having the same first reference
label irrespective of the second reference label, or other subsequent reference label.
[0235] The description set forth herein, in connection with the appended drawings, describes
example configurations and does not represent all the examples that may be implemented
or that are within the scope of the claims. The term "exemplary" used herein means
"serving as an example, instance, or illustration," and not "preferred" or "advantageous
over other examples." The detailed description includes specific details for the purpose
of providing an understanding of the described techniques. These techniques, however,
may be practiced without these specific details. In some instances, well-known structures
and devices are shown in block diagram form in order to avoid obscuring the concepts
of the described examples.
[0236] The description herein is provided to enable a person skilled in the art to make
or use the disclosure. Various modifications to the disclosure will be readily apparent
to those skilled in the art, and the generic principles defined herein may be applied
to other variations without departing from the scope of the disclosure. Thus, the
disclosure is not limited to the examples and designs described herein, but is defined
by the broadest scope as defined by the appended claims.